Wild Animals As Pets

WILD ANiMALS AS PETS

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(Taken from the Arizona-Sonora Desert Museum Docent Information sheet "I Want One for a Pet", edited and adapted to Austin by Nancy Charbeneau) We often hear children and adults asking about obtaining a wild animal as a pet. Here are a few facts and figures about the wild animal pet business to use when dealing with questions about this sort of thing. . 1. 90% of the exotic animals bought in this country are not in their original homes .,

wi thin six months after their purchase. They have either died or their owners have gotten rid of them in one way or another.

2. Keeping a wild anjmal "pet" at home creates many unforseen ·problems. The owner will never be able to domesticate the anjmal's wild instinct. ·Sudden noises, strange persons, accidently stepping on the an;mals' tail, etc. may cause it to lash out and severely injure someone. 3. Many wild animals are difficult or impossible to house train. Many wild animal s are nocturnal. While the owner is trying to sleep, the "pet" is in the midst or its active time. Many wild animals are quick to learn about opening drawers and cupboards and appear to -take great delight in scattering the contents everywhere. 4. The expense of owning a wild animal is often much more than th~ owner expected as he must build special cages and replace household items that have been broken, chewed or defecated upon. Vet bills and maybe lawyers fees (if the animal has bitten someone) add to the costs. :

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5. When the owner has bad enough and wants to get rid olthe anjmal , what happens? A "domesticated" wild animal cannot be returned to the wild and still survive. Zoos are hesitant about taking them, for these anjmals are often. in poor health, spoiled, and often incapable of mating after being away from others for a long time. Euthanasia is usually the only answer. 6. The care and feeding or aoue anjmals is often a great deal more involved than that of the conventional household pet. The exotic anjmal owner, in many cases, is completely unaware of how to feed or manage his new "pet". Wild anjmals are susceptible to rickets from lack of vitamins and minerals. Exotic animals exchange diseases sometimes with humans. 7. Keeping a wild anjmal may be illegal! In Texas most wild mammals, birds, and some reptiles are protected by state and/or federal laws and you must have a permit to keep most of them. European ferrets can be legally sold in pet stores but skunks and raccoons may no longer be purchased due to the diseases they can carry (rabies and distemper).

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8. Then there is the moral aspect of keeping wild animal pets. In order for an animal to be brought to the U.S., an untold amount of slaughter and·suffering has taken place between the animals' native home and here. The mother animal is usually killed so the young may be taken. By the time the young animals arrive in America, many have died from improper handling (as much as 80% in some cases). In other words, by purchasing a wild animal, you are ordering the death of a number of the same species. 9 . Not all wild animals are purchased. Often a YOWlg animal IS foUnd in the wild and brought home. By removing that animal from the wild, the natural cycle of events is in some small way being disturbed. Each animal has a niche to fill, and it is important that the animal is there to do that job. 10. It is also important to remember that animal parents rarely abandon their healthy offspring; they may be nearby waiting for you to leave, or out foraging for food. Also, baby birds will not be neglected if touched by a human, as birds have only a minimal sense of smell. Mammals can also be returned to the nest if they have not been handled too much. Don't rescue an;mals unless you are sure the parent has been killed, the animal appears to be cold, weak or injured, or in obvious danger. Then call Wildlife Rescue Inc (472·wn..D) for information on how to help the animal.

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Wildlife Enemies

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(add to your Urban Wildlife description, laminated sheets in boxes)

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Problem:

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Yogurt CUpS: Animals will jam their head inside to get food, but are not able to pull their head back due to design of cup. Solutioll: • Crush the cup Problem:

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Mylar: Does not biodegrade. Floats on top of water and marine animals think

it is food. When they ingest it, their intestines get blocked. Solution: • Use wildlife-friendly decorations Problem:

• Plastic bags: Do not biodegrade quickly. Sea turtles and other aquatic animals see them floating and think they are food. Solutio,,: • Make sure your grocer uses b~egradable bags. If not, ask for paper. Problem:

• Oil: Hard to get off fur and feathers once it is OD. Can inhibit flight of birds; kill aquatic animals that are a food source for wildlife. Solution: • Recycle oil

Problem:

• 6-pack holder: Animals get the plastic caught around their mouth and can't get it off. They die of starvation. Some smaller birds and mammals get it caught around their necks and are strangled. Solution: . • Ask your parents to cut the rings. Problem:

• Styrofoam: Is not recyclable, rills up landiills, does not decompose Solution: . • Buy paper cups and plates. Use biodegradable packing peanuts. Problem:

• Batteries: Chemicals (mercury, zinc, silver, lithium, cadmium) can leak out and contaminate soil and water. Solution: • Dispose of at Hazardous Waste Recycling Center

What Can I Do For Wildlife? START A LITTER CL~~ CAMPAIGN. Trash scatired along roadways and trails leads rats ~to the wilds where they destroy bird nests and eat food needed by ~ther wildlife. Deer die from eating discarded photo·negatives. Large fish have been killed by swallowing the. pull.tabs of pop-top beverage cans.

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Small fish have been trapped in the same ~iD of can when it was dropped into river. Geese and other birds hav~ drowned or starve after becoming caught in the loops of the plastic form made to hold six such cans together. Birds alre also found dangling from tree limbs hopelessly entangled in old fish line.

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REMIND SMOKERS TO USE THE ASH TRAY. Grass, weeds, and shrubs are important hiding and nesting places for small animals and birds. The seeds and ber~ies of the low-growing plants provide vital winter food. All too often such habitat is destroyed by fire. In fact, 9 out of 10 fires are caused by .,-human carelessness •

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WARN OTHERS--AND SET A GOOD ~'E V"Y'm~'~ F, TO ,STAY }J~AY FROM ALL BIRD NESTS FOUND.

Raccoons and o~her predators have long known that they can alway, find food by following human scent. Touching a nest is like saying to a raccoon, "Come and get it!"

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DON'T LET ANYONE PICK UP AN· "ORPHAN FAWtl. " A fawn hidden in the woods im r t abandoned.

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It was hidden there by its mother, and that's where she will expect to find it when 'she returns to give it milk.

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DON t T LET ANYONE ABANDON, A PET IN THE WILDS.

"Dogs or cats turned loose to live- off the country usually starve. Frequently they return again and again to the place where faithless masters left them.

ARE PROTECTED

BY LAW. There is no such bird as a "chicken hawk. tt

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Sometimes, however, the desperate animals become adept killers and are very hard on wildlife.

L iL EVERYONE THAT ALL RAPTORS

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TELL OTHERS tolHY IT IS A MISTAKE TO FEED OR MAKE PETS OF MOST WILD ANIMALS. Tae food given such animals is usually poorly suited to their needs. And not only do the animals become dependent on humans that are kind but trustful of those that are not. Also, as some wild·pets mature, they became uglytempered, even dangerous.

Below are several more ways you can belp wUdlife: Nesting baskets for owls can be made of heavy-gauge hardware cl~th or poultry wire.

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Nail kegs make excellent dens for raccoons or squirrels. Also they make good places for some hawks and owls to nest.

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Overlap edges and fasten to form a shallow Nail in crot ch Load ~th

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Adaptation - a physical or behavioral characteristic of an organism that improves its chance of survival in the environment it inhabits Aerial - spending most of the time in the air Air Sacs - openings in the bones and muscles of birds which are fille2- with part of the respiratory system . Aguatic - living in the water Arboreal - living in the trees Camouflage - a type of adaptation where the organism's outer covering blends in with its natural surroundings Carapace - top shell of a turtle Carnivore - a meat eating animal Cold Blooded - see Ectothermic Diurnal - active during the day Ecology - the study of relationships between living organisms and their environments Ectothermic - having a body temperature near to that of the environment not internally regulated (cold-blooded) dependent on external heat sources (sun) for raising body temperature Endangered - an organism in danger of becoming extinct Endothermic - able to maintain a relatively high and constant body temperature independent of the surrounding (warm-blooded) Environment - the collective term for the conditions in which an organism lives, e.g., temperature, light, water, and other organisms Estivate - becoming inactive due to extreme heat Extinct - gone forever, none left Habitat - the natural home of an animal where it is normally found Herbivore - a plant eating animal Hibernate - becoming inactive due to extreme cold Jacobson's Organ - smelling organ in the roof of the mouth of some reptiles Mammary glands - glands in mammals which produce milk Migration - the periodic movements of animals to new areas or habitats Metabolism - a process whereby food is converted into energy, stored or used to build new cells Molt - to shed an outer cover periodically Musk - a scent produced by mammals of the Mustelidae family (skunks, weasels, ferrets), used to attract mates mark territory, or in some cases, for defense Niche - an animal's job in its environment

Nocturnal - active at night Omnivore - an animal that eats both meat and plants Plastron - bottom shell of a turtle Predator - an animal that hunts or traps other animals for food Preen gland - an oil containing organ located at the base of the tail of most birds Prey - an animal eaten by another animal Scavenger - an animal that eats dead animals Scutes - the scales covering a turtle's shell Species - a group of closely related organisms potentially able to breed with one another Terrestrial - living 011 land or on the ground Territory - any area defended by an animal Threatened - refers to organisms that have been so depleted in number that becoming endangered is likely Venom - poison produced by some biting and stinging animals, such as snakes, bees, and spiders Warm-Blooded - see Endothermic

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1. These vertebrates have hollow bones. (birds)

2. These vertebrates are warm-blooded, (birds, mammals) 3. A turtle is an example of this group of vertebrates. (reptiles) 4. The largest animal ever to live is a member of this group. (mammals -- blue whale) 5. These vertebrates are cold-blooded. (fish, reptiles, amphibians) 6. Only these vertebrates have hair. (mammals) 7. All of the vertebrates in this group nurse their young. (mammals) B. This is the only group of vertebrates that has feathers. (birds)

9. These vertebrates have scales and lay eggs that usually have a leathery skin. (reptiles) 10. A few lay eggs, but almost all give birth to live young. (mammals) 11. Sweating helps keep many of the vertebrates in this group cool. (mammals) 12. These vertebrates have air sacs attached to their lungs. (birds) 13. These vertebrates have a muscular diaphragm that helps them fill their lungs with air. (mammals) 14. These vertebrates have the most fully developed brains. (mammals) 15. These vertebrates have different kinds of teeth for eating different kinds of food. (mammals) 16. Many of these vertebrates have oil, milk, sweat, and scent glands in their skin. (mammals) 17. These vertebrates do not have teeth. (birds)

IMPORTANT POINTS

ANlMAIJBIRD TOUR

All grades Characteristics - reinforce basic characteristics of mammals, reptiles and birds. Observation - have children observe differences between animals from enclosure to enclosure.

Habitat - ask children where they think this animal would live in the wild. Food - observe what food the animals have in their dishes or ask what children think they would eat.

28 minutes total time. Next station -- Mammals.

M{JM!JLL !JI!l)!Jl!PTJlLq'JCY.J{S BACKGROUND INFORMATION

I. Definitions " An adaptation is a physical or behavioral characteristic of an organism that improves its chance of surviving and reproducing ~ the environment it inhabits.

Adaptations can be: 1. an bnmediate response or 2. A response over time which is seen as the evolution of an organism's physical or behavioral traits. An example of an immediate response: shivering in response to cold or sweating in response to heat Not all organisms can make that immediate response. A turtle can't shiver. The ability to easily adapt to weather changes has been very important to humans and has made humans adaptable to many different climates. When we shiver our body is responding to the cold and causing the muscles to work, therefore wanning the body up. When we sweat our body is working to cool itself off, to regulate it's temperature of 98.6 degrees. An example of a response over time:

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A) Physical Fox ears have made physical adaptations depending on the type of environment a fox lives in. A kit fox that lives in the desert has large ears to radiate excess heat and help them to hear at night. An arctic fox has small ears so that they don't lose heat. _ B) Behavioral White-tailed deer have made behavioral changes in their feeding ha.bi1s..~ecause of humans. They used to feed during the day, but now they feed at nigh~" to avoid human contact (hunters, etc.). -"

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III. Predator/Prey Relationships Every animal on this earth shares a common problem. It must get enough nourishment to keep its body going or else face death. Herbivores, the hunted or prey, are animals that depend on plants for their food. Carnivores, the hunters or predators, largely depend on herbivores to supply their food, and omnivores eat both plant and anima! matter.. Predators and prey are constantly adapting to each other as much as to their physical environment. As the prey gets better at hiding, the predator gets better at rmding them. As the prey develops better defenses, the predator finds ways of getting around those defenses. For example, a porcupine's quills can keep away wolves and coyotes, but mountain lions and pine martens have learned to reach under the porcupine to it's belly where there are no quills and rip it open. If you look at a ferret and a rabbit you can see general characteristics of predators and prey

animals. . PREDATORS tend to bel have: * curious rather than timid. They must investigate every possible channel lhat might yield food; * quick, restless, energetic and alert movements; * well developed sense of smell; * binocular vision (depth perception); * strong jaws and sharp teeth.

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PREY animals tend to bel havel do: * well developed sense of hearing with large ears; * eyes on the sides of the head; * unaware of an object until it moves; * good sense of smell; * travel in numbers for safety; * dive for cover or stand motionless (freeze); * protective devices such as quills, armor, spray.

IV. Defense Mechanisms Hair or skin modifications: quills (evolved from hair, soft to thick) coloration for camouflage (also found in predators) ann or Tooth modifications: tusks (elephant, walrus, narwhal) canines HQrns and Antlers Poisonl Deterrents: (skunks, venomous snakes- specialized saliva)

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Warning: . \\ ~ coloration- monarch butterfly, coral snake .. behavior- rattlesnake rattle (evolved from build up of unshed skin), skunk taps paws on ground Deception: (owls- puff themselves up to look bigger- spread either one or two wings; opossum- play dead; moth with eyespots; alligator lizard- makes tail seem alive after fleeing to safety) Mimicry: (Mexican Milksnake, Viceroy butterfly)

V. Finding Food Beaks Teeth Feet

IV. Feathers have been adapted for many different functions. A. Physical types 1. Flight

2. Contour 3. Downy

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4. Specialized a. Woodpecker tail spines (to prop against tree to assist in balance) b. Owl primary feathers ( zippered to aid in silent flight) c. Peacock taiYfan (for males to attract a mate) d. Owl "whisker" feathers (to help feel food) B. Coloration 1. Camouflage 2. Deception (peacocks and "eyespot" feathers) 3. Mate attraction

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(15 minutes)

Define Adaptation: A CHANGE TIlAT ALLOWS A PLANT OR AN ANIMAL TO SURVIVE AND REPRODUCE. Discuss Immediate vs. Long-term Responses & Physical vs. Behavioral: -What would" your bodies do if I sent you to run around the playground 10 times on a hot <;lay (SWEAT!) What would your bodies do if you went camping in the Arctic and forgot to bring a coat? (SHIVER) THESE ARE EXAMPLES OF AN IMMEDIATE RESPONSE

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-show pictures of elephant trunk or giraffe neck THESE ARE EXAMPLES OF PHYSICAL ADAPTATIONS -A physical adaptation is something you can see/ measure. An elephant's trunk is a physical adaptation that occurred over time. The length of the trunk is a physical change that we can measure. It's also a change that took a very long time to happen. Probably one elephant was born with an unusually long trunk- which turned out to be a very good thing, because that elephant could reach higher plants to eat than any of the other elephants. So that one elephant with the long trunk got to eat more, be healthier and have more babies than the other elephants. The long trunked elephant passed along that long trunk to all of its babies. And since they could reach higher plants, they were healthy, had lots of babies and passed along their long trunks. The elephants with the shorter trunks sometimes had to go hungry because they couldn't reach the plants. So those elephants didn't have enough energy to make babies and their short trunks didn't get passed along to the next generation. Pretty soon all of the elephants had long trunks. Then one was born with and even longer trunk and it all started again. After many thousands of years a regular nose became a long trunk. " THIS IS AN EXAMPLE OF A LONG-TERM RESPONSE

*ACTIVITY: Can you think of any way that humans have pbysjcally adapted to surviving? Hint- think about our hands and different fingers Ask for a couple of volunteers. (Wear animal puppet on your hand) Shake their hand with the puppet, have them introduce themselves to the puppet and the group. Yank or joke about their thumb, what a funny finger," what good is it, why does it stick off the side of their hand like"that? Ask them to extend their hand and tape each child's thumb to the inside of their palm. Then ask them if they would be willing to be your helper. Tell them to pick up various objects both big and small. Ask the group what the problem is- why is the helper having trouble? Talk about thumbs as a physical adaptation and the importance of thumbs for everyday life. NOW AN EXAMPLE OF BEHAVIORAL ADAPTATION: Does anyone kno,v when deer eat? Show picture of deer At night. Well they haven't always eaten at night. Deer used to eat in the daytime. Who has an idea about why they might have changed their behavior? -Because people shoot them in the day time. It's against the law for people to go out at night with spotlights to find deer an kill them. So deer started going out at night to feed. In the daytime, they lie quietly in the woods and try not to be noticed. This is a behavioral adaptation- you can't measure the differences like with an elephant's trunk. Reiterate that an adaptation is something that helps an animal to survive and it can be a physical or a behavioral response .

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Reasons for High Adaptability (10 minutes)

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Go through the reasons for high adaptability by showing pictures. Four thing~make animalsmore able to adapt and survive: 1) Short life cyclesl rapid reproduction- insects vs.~ea turtle Do you think a sea' turtle has lots of babies each year? NO, that is one reason that sea turtles are endangered species (they are in danger of becoming extinct). ' Do you think this insect does? ____ ' .' 2) Using Intelligence oyer instinct- American crow vs. GQJ.~en CheekeCl- C:~,",l..... ~~ '- . ... warbler) Crow uses intelligence to help find alternative nest building materials People use intelligence too. We make blankets, coats, heaters, ice, air-conditioners, etc. 3) Diet- ('.~c \,\)~.s,-\.,v .... ,~?i~\..b-"l~V' An animal that can eat plants or meat or scavenge for just about anything can survive better than an animal that only eats one type of food. 4) Mobility- batlbirdlinsects

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Birds, bats, and insects are very successful because they can go from one habitat to another. If a habitat is destroyed or polluted, these animals are able to move to a more suitable habitat. Other animals that can't fly may be stuck in that bad environment.

OTHER ADAPTATIONS

(15 minutes)

,/f/.t ~,~ cV\atJ~ . Show· various specimens and explainllet children explain how they help the animal to survive: encourage discussion- DEFENSE, FEEDING

Hair/skin quills turtle shell armadillo shell ,:,ari~~s ~el:!flage/wamiftg fur ~ \(f~~.l\i\(,'-

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Teethl skulls '

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pictures, of tusks (elephant, walrus, narwhal) herbi vore skull carni vore skull omnivore skull

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Horns/ Antlers pictures

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Poison/Deterrents skunk snake

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Warning white-tailed deer coral snake

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Feathers warmth downy flying flight defense (camouflage) flight & contour attracting a 1nate (large eyespot may deter predators) peacock

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Another kind of adaptation is mimicrJ. Who knows what it means to mimic something? To copy or pretend to be...

Mimicry Mexican milk snake Viceroy Butterfly

mimics coral snake mimics Monarch

-The Coral snake is a venomous snake that has red, yellow and black bands all around it's body. But not all snakes with red, yellow and black bands are poisonous. There is another snake that looks a lot like the coral snake and is not venomous, does anyone know the name of that snake? Does anyone know the jingle/ rhyme we use to help us remember which one is dangerous? (Red and yellow kill afellow; red and black poison lack) The snake with the red band touching the yellow band IS poisonous the snake with the red touc~ng the black IS NOT poisonous. Do you think that animals learn this rhyme? No, animals just learn that those colors signal danger .. So most animals stay away from all snakes that are red, yellow, and black... and many of the snakes they are avoiding aren't venomous. Those non-venomous snakes are adapted to look like the venomous ones. . This is an example of mimicry.

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-The monarch butterfly is a butterfly that birds don't eat because it tastes bad. The monarch eats nectar from milkweed plants which taste really bi ner and make the butterflies taste bad to the birds. Have you ~ver eaten a monarch butterfly? Well, there's another butterfly called the viceroy that does not eat milkweed and it doesn't taste bad. But the viceroy does look almost exactly like the monarch-so birds don't eat it. If a bird catches a butterfly that looks like this, it might taste good or very bad. However, if it catches a different looking butterfly, then it will definitely taste good. So the viceroy is adapted to look like the monarch and that is another example of mimicry.

Animal Show (15 minutes) LET'S SEE ADAPTATIONS OF A FEW PARTICULAR ANJ1vIALS:

MADAGASC·AR HISSING COCKROACH omnivore! scavenger live birth! ovoviviparous exoskeleton sticky feet spikes on legs hissing

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MEXICAN' MILK SNAKE mimicry legless scales! shedding smelling with tongue jawbone detachment

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ALLIGA TOR LIZARD scales/ shedding of whole skin ears tail breaks off tail is deceptive when broken off- seems alive camouflage

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ANIMAL ADAPTATIONS pROGRAM SCRIPT

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>Introductory questions (see more detailed script attached) Adaptations may be...

* Immediate or take a long period of time (shivers or sweat) (elephant's trunk) * physical or behavioral (bat's wing) .: •(feeding habits of deer)

Things that usually aid in survival or make an animal more adaptable: - short life span and high. reproduction rate ex: Insects, such as mosquito developing a better stinger - use of Intelligence over Insflnct 1 ex: vireo nest building vi. crows building from scavenged Items ~... - dietary generalists ex: opposums and raccopns succeeding In urban areas - highly mobile, especially abiOty to fly ex: bats, birds qnqJnsects 'colonizing many habitats. :'

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Predator vs. Prey type of beh'aviors discuss porcupine, show .-tit.quills and lead Into defenses

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Defense: Behavior»>kllldeer with fake wing injury, deer flashing white tails, elks butting antlers ! Structural»>mountaln lion c~aws, turtle shells, bird of prey talons

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Food Finding»>feet and beak posters, snake skull, mammal herbivore and carnivore skulls Feathers»>downy feathers for warmth , flight feathers for flight and water repellence and camoflage peacock feather for attraction of mate and possibly to deter predators Mimics: butterflies»>monarchs taste bitter because they eat milkweed; viceroys taste fine, but look like monarchs so don't get eaten snakes»>coral snakes are venomous; milk and king snakes are not, but look similar to coral snakes so don't get bothered

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Roach ••• omnivore, live birth, exoskeleton, stiCky feet, spiked legs Owl··· nocturnal, predatoL superior eyesight and hearing, talons, beak Skunk .** stripes, stamps, spray, nocturnal, omnivore, sense of smell Opossum *.* nocturnal, omnivore, marsupial, tall and feet for climbing, ·playlng 'possumD Milk Snake legless, earless, no eyelids, jaw detachment, constriction, color pattern

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ANIMAL ADAPTATIONS SCRIPT

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These are Introductory questions. Just to make sure everyone Is at the same leveL. What Is an adaptation? A change that allows a plant or an animal to survive and reproduce. What Is a reptile? a bird? a mammal? What does It mean to be an ectotherm? an endotherm? What Is a predator? prey? "

Adaptations - those changes that allow the organism to survive and reproduce - may be Immediate or they may occur over a long period of time. . An example of an Immediate [esponse would be If we sent you outside on a hot day to run around ltie.~lock three times ... what would your body do? Sweat. Sweat is your body's response to cool Itself. You don't think about it, It just happens as an Immediate response to cool you off. Or If you went outside on a verY cold day naked ... what would your body do? It would get goose bumps €Jnd shiver. Those muscle movements produce heat tp tty to warm you up. This is also an immediate response of your bddy to Its environment. Adaptations may also be physical or behaylorgl. A physical adaptation hr.$omethlng you can see/measure. An elephanfs trunk Is a physical· adaptation < elephant picture> that occurred over time. The length of the trunk is a physical change that we can measure. It's also a change that took a very long time to happen. Probably one elephant was born with an unusually long trunk - which turned out to be a very good thlng~ because that elephant could reach higher plants to eat than any of the other elephants. So that one elephant with the long trunk got to eat more, be healthier and have more babies than the other elephants. The long trunked elephant passed along that long trunk to all of its babies. And since they could reach higher plants, they were healthy, had lots of babies and passed along their long trunks. The elephants with the shorter trunks sometimes had to go hungry because they couldn't reach the plants. So those elephants didn't have enough energy to make babies and their short trunks didn't get passed along to the next generation. Pretty soon all of the elephants had long trunks. Then one was bom with even longer trunk and it all started again. After many thousands of years a regular nose became a long trunk. Deer have a behavioral adaptation. Does anyone know when deer eat? < deer picture> At night. Well they haven't always eaten at night. Deer used to eat in the daytime. Who has an Idea about why they might have changed their behavior. Because people shoot them in the daytime. It's against the law for people to go out at night with spotlights to find deer and kill them. So deer started going out at night to feed. In the day time, they lie quietly In the woods and try not to be noticed. This is a behavioral adaptation - you can't measure the differences like with an elephanfs trunk, but it Is definitely an adaptation to living In a well-armed society. 1

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Four things make animals more .able to adapt and survive: (1) • Living a short life and reproducing quickly - do you think an elephant <elephant picture> has lots of babies every year? - do you think a mosquito does? So how much faster could a mosquito pass along an extra large stinger than the elephant passed along Its trunk? (2) • Using Intelligence over Instfnct qlone - black-capped vireo uses Instinct only In nest building (and Is endangered) < vireo picture> - crow uses Intelligence to help find alternate nest building materials. < crow picture> - people use Intelligence, top. To help us survive In all climates, we make blankets, coats, heaters, Ice and airconditioners. . ,.... (3) • Being a dietary generalist - an animal that can eat plants or meat or scavenge for Just about anything can survive better than an animal that only eat~.o~e type of food. (4) • Being highly mol?ile,~especlally fliers - birds, bats < bat pictures> and Insects are very successful because they can go from one habitat to another. If a habitat is ,d§stroyed or polluted, those animals are able to move to more suitable habitat. Other animals that can't fly may be stuck In that bad environment. So a (1) short life (2) Intelligence (3) being able to eat lots of things and (4) being able to fly are .thlngs that help animals to survive. r

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Let's look at some defensive adaptations: Behavioral: • Killdeer dragging wing to divert < killdeer picture> predators away from eggs/nest. , • Deer flashing white toils as a warning signal to others. <deer tail p.ctur~> • Elk butting heads to defend territory or mates. < elk picture> Structural: • Quills of a porcupine to protect it from predators. • Talons of birds of prey for catching food, perching and defense. < owl talon> • Turtle shell ... same defense for many millions of years because Irs such a successful adaptation, no need for a new and Improved version of the turtle. -< shell >

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Some adaptations are for getting food: • Look at examples on feet and beak posters • Look at mammals with carnivore, omnivore and herbivore teeth < skulls of deer and bobcat and opossum > • Look at snake skull and point out ability to detach at joints and eat large prey.

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Feathers are highly adapted Items also: • Downy feathers are for warmth • Flight feathers are for flying • Flight and contour feathers are for camouflage • Peacock feathers are used In attracting a mate (also the large eyespot may deter predators) Another kind of adaptation Is mimicry: Who knows what It means to mimic something? To copy or pretend to be ... • The monarch buHerfly < picture> is a butterfly that birds don't eat because It tastes bad. The monarch eats milkweeds which taste really bitter and make the butterflies taste bad to the birds. Have you ever eaten a monarch butterfly? Welf t.her~'s another butterfly called the viceroy that does not eat milkweed ·CJn~ It doesn't taste bad. But the viceroy does look almost exactly like tHe monarch - so birds don't eat it. If a bird catches a butterfly that looks like these, it might taste good or very bad. However If it catches a' dlff~rent looking butterfly, then it will definitely taste good. So the vlcer6y Is adapted to look like the monarch and that Is an examQle of mimicry. • Another kind of mll'l1Jcr{ Is the snakes that are these colors < rubber coral snake>. One kind of red, yellow and black snake Is venomous. All of the other kinds of red, yellow and black snakes are not venomous. Does anyone know the rhymewe use to help us remember which one is dangerous? (Red and yellow kill a fellow; red and black poison lack) Do you think animals learn that rhyme? No. Animals just learn that those. colors signal danger. So most anlm'als stay away from all snakes that are red, yellow and black ... and many' of th~ snakes they are avoiding aren't venomous. Those non-venomous snakes are adapted to look like the. venomous ones. That is mimicry. Now let's look at the adaptations of a few particular animals: (It's probably best to use just one Insect, bird, mammal and reptile) • Cockroach • Skunk > omnivore / scavenger > nocturnal > live birth -/ OVoviviparous > omnivore > exoskeleton > senses: smell and touch > sticky feet > striped for visibility > spikes on legs > (behavioral) stamping front feet > hissing > spray (adapted from scent marker)

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• Screech Owl > nocturnal > predator / carnivore > vision / head rotation > sense of hearing > talons > beak > camouflage > small size

• Opossum > nocturnal > omnivore > marsupial > tail and feet for grasping > Iplaylng 'possuma

• Milk Snake > mimicry > legless > scales/ shedding > smelling w/tongue > Jawbone detachmnt 3

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Article by Leslie Day, Drawing by Jonah Nishiura

EARTHWORMS: Lumbricus terrestris "It may be doubted whether there are many other creatures which have played so important a part in the history of the world" Charles Darwin, 1881 Some scientists estimate that there are approximately 50,000 earthworms per acre of moist soil. Earthworms live in deep, dark, long, and narrow tunnels or burrows under the ground, They cannot tolerate heat and sun and so during the summer they come up to the surface only at night. They also leave their burrows when it rains because it is easier for them to move on the wet surface. After a rain you will notice multitudes of earthworms on the surface. The wet ground allows them to mo:ve without drying out.

BENEFITS OF EARTHWORMS: Gardeners, fanners, foresters and soil scientists all love the

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earthworm because of the good they do for flowers, crops, and plants and animals of the forest. Earthworms are active animals and feed by bringing organic debris into their burrows from the surface and by eating their way through the soil. The leaf litter (dead leaves and animals) they digest' contains nutrients made by plants during photosynthesis and includes calcium, nitrogen, potassium and phosphorus, and organic minerals and nutrients from dead animals. Their excrement, called castings, is deposited on the surface and is rich in nutrients, providing food for other animals and microorganisms. This organic material is then further broken down by microorganisms of the soil, releasing nutrients in a form available for absorption by plants. In this way, earthworms have helped produce the fertile humus that covers the land. As a result the layers of soil are thoroughly mixed, seeds are covered and enabled to germinate, and over long periods of time stones and other objects on the surface are buried. This process has even buried and preserved ancient buildings. Each year earthworm castings cover each acre with as as much as 18 tons of rich soil.When earthworms die, usually in the dry summer, the organic material making up their bodies is gradually released providing additional nutrients for plants. These minerals are essential to healthy plant growth.

EARTHWORM BURROWS: the tunnels earthworms make beneath the topsoil do a tremendous service to the trees and plants above. Their burrowing aerates the soil, which is why earthworms are called "nature's plough". They not only help bring oxygen down into the soil, but their tunnels allow rainwater carrying organic and inorganic nutrients down deep into the soil where the roots lie. The roots then take up the water and the minerals and recycle them back to the herbaceous plants and woody trees.

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DESCRIPTION: If you watch an earthworm move, you will most likely see it move forward, with its pointy end in the front. This is its mouth and prostomium (area in front of the mouth). There is a concentration of sensory cells at this anterior end around the prostomium. And though it has no eyes, it possesses light sensitive cells and can "sense" light. As mentioned above, it cannot hear, but feels vibrations of animals moving nearby.

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Y:SIte West SIde - .Earthworm

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The worm's body is divided into 100 or more body segments. As the worm works its way·forward, successive peristaltic or contracting waves of thickening and thinning (7-10 per minute) pass down the body. At each place where the body bulges out at a given moment, the bristles, or setae, are extended and grip the burrow walls. Setae, which are not true legs but pairs of bristles attached to each segment, push against the ground with each contraction and help the animal move.

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When a Robin tries to pull an earthworm out of the ground, the worm uses these bristles to hold on tight to the wall of its home. Sometimes the worm holds on so tight and the Robin pulls so hard that the worm comes apart. The Robin keeps the front end and the hind end wriggles back into its burrow. If a bird pulls off the first 7 or 8 rings of the worm's body, new segments will grow. If a worm is pulled in half, the head end will grow back. The earthworm has no lungs and takes in oxygen through its moist skin - it is a skin breather. If it dries out it will suffocate. Its skin is covered by mucus-secreting cells. The mucus serves not only in respiratory exchange, but it also lubricates the worm's body and eases passage through the burrow. The mucus covered skin helps bind soil particles together and prevents the walls of the burrow from . collapsing.

LIFE CYCLE: Earthworms are hermaphrodites with both male and female reproductive organs. On warm, moist spring and summer nights, you can often seen hundreds of mating worms coming up out of their burrows. Once they have mated, the girdle like ring around the front of an earthworm, called the clitellum slides along the worm's body, picking up fertilized eggs. When it finally falls off the worm into the soil, it forms a well protected nest or egg case within which the embryo worms develop.

PREDATORS: Because the body of the earthworm is 70% protein, they are a sought after prey by birds, especially Robins, and by burrowing animals like moles. If you watch a Robin hunting, it pauses, cocks its head, then strikes with its bill, pulling a worm from the ground. The Robin, with its keen eyesight, detects the earthworm's movement in the grass. The earthworm, both sightless and ear-less, can feel the vibrations of the bird on the surface of the ground.

mSTORY: Earthworms were brought to North America by the early European settlers in the 17th and 18th centuries. If earthworms existed in North America prior to this, they were probably wiped out during the last ice age, 10,000 to 50,000 years ago

BIBLIOGRAPHY: Earthworms, Dorothy Childs Hogner, 1953, Thomas Y. Crowell, New York

Earthworms, John Mertus, 1993 Living Invertebrates, Editors Pearse and Buchsbaum, 1986, Boxwood Press, Pacific Grove, Ca.

NYSite Home I Nature Home I Animal Guide I Sprine Guide I Summer Guide I Fall Guide I Winter Guide

This article has been prepared by the 79th Street Boat Basin Flora and Fauna Society. If you are interested in the plants and animals of the river and Riverside Park, you can write to us at Box 9, 79th Street Boat Basin, NY, NY 10024. Copyright © 1996 The 79th Street Boat Basin Flora and Fauna Society

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10110/2005

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· Kea Harvester Ants

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Texas Agricultural Extension Service

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The Texas A&MUniversity System

Red harvester Ants

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u Bastiaan M. Drees Professor and Extension Entomologist The Texas A&M University System Red harvester ants are one of the more noticeable and larger ants in open areas in Texas. However, harvester ants are not near-Iy as common today as they were during the earlier 1900s. The decline, particularly in the eastern part of the state, has caused some alarm because these ants serve as a major source of food for the rapidly disappearing and threatened Texas homed lizard.

Description Worker ants are 1/4 to 1/2 inch long and red to dark brown. They have squarish heads and no spines on the body. There are 22 species of harvester ants in the United States, 10 of which are found in Texas. Seven of these species are found only in far west Texas.

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Ked Harvester Ants

Red :batYeSter·ants

Life cycle Winged males and females swarm, couple and mate, especially following rains. Winged forms are larger than worker ants. Males soon die and females seek a suitable nesting site. After dropping her wings, the queen ant digs a burrow and produces a few eggs. Larvae hatch from eggs and develop through several stages (instars). Larvae. are white and legless, shaped like a croolmeck squash with a small distinct head. Pupation occurs within a cocoon. Worker ants produced by the queen ant begin caring for other developing ants, enlarge the nest and forage for food.

Pest status Worker ants can give a painful, stinging bite, but are generally reluctant to attack. Effects of the bite can spread along lymph channels and can be medically serious. Harvester ant workers commonly are sold for ant farms.

Habitat Worker ants remove vegetation in circular areas or craters around nests. Colonies occur in open areas and usually have a single central opening. The area around the opening usually has small pebbles deposited on the soil surface by the worker ants. Often there is no vegetation within a 3- to 6-foot circle around the central opening of the colony, and along foraging trails radiating from the colony. Colonies usually are widely separated; however, heavy infestations in pasture and rangeland can reduce yield. Red harvester ants also colonize in ornamental turf areas where their presence may be undesirable. They do not invade homes or structures.

Food sources Red harvester ant foragers collect seeds and dead insects and store them in the nests as food for the colony. The ants' mouthparts are designed for chewing.

Management Red harvester ants are native species and are generally not considered to be serious pests. Consider

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• Ked Harvester Ants

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the option of not controlling these ants, especially in areas inhabited by the few remaining homed lizards (see box).

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However, in certain cases, elimination of red harvester ants may be necessary. Destruction of their nests and habitat through regular discing and mowing may eliminate them without resorting to use of insecticides. If pesticides are selected, use registered products selectively and carefully follow instructions provided on the label. Although any insecticide registered to control "ants" can be used to control harvester ants, few are registered specifically to control these species. Harvester ant colonies can be quickly eliminated using Amdro® Pro Fire Ant Bait containing 0.73 percent hydramethylnon. Individual colonies can be treated using 2 to 5 tablespoons of product scattered around the colony's central opening. In larger areas, the product can be broadcast at a rate of 1 to 1 1/2 pounds product per acre (2 to 3 ounces per 5,000 square feet) using a suitable application device such as a hand-cranked seeder or the electric-driven mountable Herd GT Model 77 Seeder. Amdro® can be used in lawns, landscaped areas, golf courses, other noncropped areas, grounds surrounding poultry houses, corrals, other animal holding areas, nonbearing ornamental nursery stock, pasture and rangeland. Do not cut and bale hay from treated cattle pastures and rangeland until 7 days after bait application. In noncrop areas, acephate dust products such as Orthene® Turf, Tree & Ornamental Spray (75 percent acephate) can be applied as a dry application of 1 to 2 teaspoons product per nest. It also can be applied as a liquid drench, using 1 ounce of the product mixed in 5 gallons of water. Apply the mixture at a rate of 1 gallon per mound plus a 4-foot diameter circle around the nest.

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Help Save the Texas Horned Lizard

u The Texas homed lizard is a protected threatened species. It is commonly called "horny toad."

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As primarily sight oriented creatures, we utilize hearing as a secondary sense. But for nC?cturnal creatures, hearing serves many important primary functions such as detecting prey, escaping from predators, finding a mate, or even navigating!

Remember the riddle, if a tree falls in the forest and their is no one there to hear it, does it make a sound? The answer is yes. Sound is a physical phenomena produced by rapid minute changes in the surrounding medium which originate from a vibrating source and propagate outward in waves. According to that definition the answer to the riddle would be yes.

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Sound is measured in decibels, which is the loudness of the sound and in cps, (cycles per second) which is the frequency of the sound. The range of human hearing is from 16 cps to 30,000 cps, with 20,000 cps being the upper limit for most adults and 23,000 the upper limit for children. For comparison, Middle C on the piano is 256 cps. A bat hears 100,000 cps, with a top limit of 300,000. Most birds probably do not hear above 10,000 cps. An example of a simple ear is found in the moth. The moth has one

two- celled ear on each side of the head for directional hearing. Yet, even with this s~ple system, the moth can derive meaning from environmental sounds and respond accordingly. They can discriminate between faint and intense sounds but appear to be tone deaf. Using its sense of hearing, a moth can avoid predation by bats by detecting and responding to the high frequency pulses emitted by bats. The moth can determine the distance and direction of . the sound, i.e. if the sound is far away, the moth will fly up, if it is close, the moth will drop to the ground. Some moths can even jam a bat's frequencies It appears that mo~ only use their hearing to avoid bats.

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Crickets not only also use their hearing to escape from bats, but also to communicate with other crickets. Crickets produce sound by rubbing their wings together to produce song." Different songs are produced to lure a potential mate, communicate aggression and as advertisement of territory. The cricket listens to the songs with its legs! Two tympanic membranes on each front leg can analyze frequency and intensity of sound. A more complicated ear is found in mammals. The outer ear consists of a flap, or pinna and the ear canal leading to the ear drum or membrane itself. Beyond the ear drum is the middle ear, which is a small chamber containing three tiny bones linked together in such a way that they amplify the vibrations of the eardrum. The innermost bone, the stapes, transmits the vibrations to the inner ear which is a small coiled structure that resembles a snail shell. Inside the cochlea are membranes bearing receptor cells. Movement of the stapes agitates the fluid in the cochlea, which in tum sets off the receptor cells to send nerve impulses to the brain. The bird ear is very much like the mammalian ear except there is no pinna and the middle ear arrangement is a little different.

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Nocturnal mammals often have a very large pinna or outer ear to help amplify sound and judge direction. Often the pinna will be quite mobile. Sometimes it may be naked like in the opossum. Mice and rabbits have large pinna to detect predators. On the flip side of the coin, cats use their ears to detect the sounds of prey. They can rotate their pinna almost 180 degrees to help pinpoint the location of the sound. Because they rely so much on their hearing to hunt, they have heavily padded and furred paws to muffle their own sounds. In Africa, the oversized pinna of two nocturnal animals, the Bateared fox and the Aardvark, allow both to listen to the sounds made by their favorite prey underground ... termites! Owls use their hearing for both hunting and courtship. It is thought that the feather tufts or "horns" of some owls may help them distinguish the direction of the sound. The facial disks of owls also may serve to funnel the sound to their ears". Some, such ~s the Barred, Spotted and Bam owls, have asymmetrically placed ears to help them pinpoint the location of sounds. The ~eft ear is placed lower than the right ear. By comparing the intensity of the

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sound in each ear the owl can triangulate the prey's position. Experiments performed with barn owls show that they can actually capture prey in a totally darkened room with an accuracy of 1.5 degrees. To aid them in detecting prey, owls have soft primary feathers that allow them· to fly without a sound. The mice with their sharp hearing can't detect them, and the owl does not have to listen through the sound of its own flapping. OWls and cats probably have the same level of hearing acuity which is about ten times better than ours. The most extraordinary sense of hearing is found in the bat. Bats use hearing for orientation and the capture of prey through echolocation (note: not all of the nearly 1,000 bat species use echolocation, it is mostly used by insectivorous bats). Echolocation allows them to fly as fast as if they were using vision and to detect animals as small as fruitflies. They can also judge an object's speed, size, distance and even texture. They emit a high pitched sound in the range of 100,000 to 300,000 cps which bounces off the object and is picked up by the bats' sensitive ears.

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Some bats, such as the Spotted bat, have incredibly huge ears. They are as long as its body! The weird looking faces of bats all have something to do with echolocation. The sounds are sometimes emitted through the nose and the odd shapes alter the sound and its direction. Bats have other uses for hearing. Mother bats that raise their babies in large nursery colonies recognize the sound of their baby. A newly discovered way bats use sound involves courtship. The author, while on a research project with Dr. Merlin Tuttle, founder and Director of Bat Conservation International, witnessed male Gray Bats that appeared to be singing in a Tennessee breeding cave.. It is not known if the singing is to announce territory to other males or to attract females. Listening to Wildlife and trying to understand the sounds they make can help humans to gain a much better appreciation and awareness of nature. Concentrating on listening skills isn't a bad idea. We can use it to be better communicators among ourselves!

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"Head.of a swine, tail of a rat, fur of a cat". So spoke Captain John Smith of Jamestown Virginia back in 1607 to describe the opossum the Algonquin Indian word for "white beast". It has also been described as having the "ears and eyes of a bat". All of these are amazingly descriptive. All in all, only the most empathetic call the opossum a "cute" creature. The opossum, North America's only marsupial (pouched mammal), used to only range as far north as Virginia (hence its scientific name Delphinus virginianus ), but with the expansion of human populations, the opossum has found its way either purposely or accidentally to California and all but the most northern states, where its naked ears, tails and toes create major survival problems.

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People have many misconceptions about opossums. Perhaps the most prevalent is that the opossum hangs upside down by their tails to sleep. This is not true. While the opossum's tail is prehensile, it is not strong enough to support the animal's body weight. It does, however, use it for balance and support while climbing. In this effort it is also aided by having an opposable thumb on each of its back feet. The tail is also used to gather and transport leaves to be used for a bed. A folktale tells of the mother carrying her tail curled over her back and the young clinging to it with their tails. This is probably an exaggerated observation. The young do cling to their mother's fur and may also grab onto the tail. Because most people find opossums flattened in the road, they think that the creatures must be incredibly stupid. Actually, as nocturnal scavengers, they are· out in the roads feasting on the road kills of the day and are blinded by the headlights. Truly, opossums are not the brightest creatures. For their size, the brain case is quite small, about the size of a pea. But laboratory tests have shown that opossums do have a remarkable smell memory. Testing well above dogs; cats, and turtles. It has an acute sense of hearing but is very nearsighted.

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Like other marsupials, opossums are born as underdeveloped embryos. The eyes, ears, rear legs are merely buds. Twenty to forty honey bee sized young are born after a gestation period of only 13 days. With only a pair of slightly developed front limbs and deciduous claws, the embryos drag themselves the two inch length from birth canal to pouch. In the pouch are only 13 pinhead sized nipples .. The first 13 latch· onto a nipple which then swells and elongates and literally becomes lodged in the embryo's mouth. The others perish. Such is survival of the fittest. Inside the protection of the pouch, the young develop and grow until they are about 70 days old, whereupon they are too big for the pouch and venture out, sticking only their heads in for a drink. After 100 days, they are weaned and on their own. Only about 50/0 of opossums live into their 3rd year. Even in captivity, an opossum has a short life span. Unlike other mammals, but similar to snapping turtles and alligators, an opossum grows throughout life, with no upper limit. Perhaps it is a good thing they have short lives! Opossums have been around for about the last 100 million years, making them real relics. They adapted to their nocturnal life as other mammals did at the time, to escape the dinosaurs. They have myopic eyesight, but do have good a good sense of hearing and as previously mentioned, an excellent sense of smell. Opossums are slow however, and they evolved some interesting defensive strategies. When an opossum feels threatened, it may first open its mouth wide, show all of its teeth and snarl. If that doesn't work, an opossum plays dead (hence the term "playing 'possum"). It rolls over, its tongue hangs out, it drools, defecates and its breathing becomes shallow. This is not a conscious act, but thought to be triggered by a shock type of reaction. H the opossum is lucky, the predator loses interest and leaves .. The opossum can remain in this state for minutes or hours. Another amaZing ability of the opossum, is that it is immune to the venom of the Crotalid snakes, that is Rattlesnake~, Copperheads and Cottonmouths. This has evolved over time having to dwell with .these snakes, as they are not immune to Cobra venom. An opossum will kill and eat a Rattler if given the chance, so much for being slow! Its omnivorous ~iet also includes bird's eggs, young mice, grubs, earthworms and other invertebrates, fruits, vegetables, carrion, and of course, human garbage.

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Your pupils are round so they can absorb as Like most humans you understand your world mainly through what you . much light as possible. But cats, crocodiles, see. Certainly you can hear, feei', and smell, but for most people, to see is geckos, lizards, and snakes all have vertical to understand. That's why we often slits in their eyes. Scientists aren't sure why, .. say, "See what I mean?" Many noctumal creatures understand the world just as well-if not better-than we but certain species, like some frogs and toads, have horizontal (sideways) pupils. do. They get around at night using various highly developed senses. So if they could talk, night ~als might say, "Feel what I mean?" or ·'Smell Night Vision Tests what I mean?" On a moonless night you may not be able to see anything When you go outside at night. you don't when you go outside, but for many creatures that same night is full of see very well at first. Why not? 1ry this: when you venture out, find a comfortable light. What is the difference between your eyes and theirs? Night Eyes

Eyeshine

Except for insects and their unique compound eyes, all animal eyes are lined with rods and cones. Cones examine detail; rods absorb light. Because you are diurnal (active in daylight), your eyes have more cones than rods. Diurnal eyes are able to distinguish small details very clearly, but only if there is plenty of light. The eyes of nocturnal animals are packed with rods and have only a few cones. Nocturnal eyes do not distinguish small details, but they are able to detect shapes and movement in dim light. Also, some animals can see fonns of light that you can't. Birds that migrate at night can see polarized light, and nocturnal insects see ultraviolet light. Many night creatures have dual purpose eyes; they are able to see during the day and night. To see well at night these animals have shiny membranes called tapeta behind their rods and cones. At night the tapeta reflect weak light back through the eye. By using light twice, the animal can see better.

When light from your flashlight or car headlight shines in the eyes of an animal with tapeta, the color of light reflected back varies according to the species. How many night creatures can you identify by their eyeshine? Fox

white yellow

Raccoon

amber

Skunk

dull orange red-orange

Opossum Flying Squirrel Black-tailed Jackrabbit

red

Porcupine

deep red yellow green-gold green

Deer CoyotelMountain Lion Domestic Cat and Dog

Snake Eyes

To protect their light-sensitive eyes, many night creatures have eyes equipped with vertical (up and down) pupils that can close to small slits during the day. This is how they prevent too much light from coming into their eyes and "blinding" them (especially if they are disturbed during the day and have to move about).

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place to stand or sit and close your eyes for a couple of minutes. When you open them, you'll be able to see better. Go outside at night with a buddy (let's call him or her Sam), and bring a flashlight. Face Sam and stand about a foot away. Thm the flashlight on and hold it down by your side so the light hits the ground. Look directly into Sam's eyes, then slowly bring the light close to Sam's eyes but don't shine it straight at them. Move it away, then repeat. What happens to Sam's pupils? While you and Sam are out checking your night vision, here is something else to try. Ask Sam to stand about 50 feet away from you. Looking directly at Sam. ask him/her to wave at you. Now, look away slightly and ask Sam to wave again. Is there a difference? There should be. You are able to detect movement in the dark much better out of the comers of your eyes because you have more rods at the edge of your field of vision and fewer cones. So if you think you see something straight ahead, look to the right or left. If whatever it is moves, you'll probably see it.

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Feathers, and Whiskers

Fur on mammals and feathers on birds help protect them, but they also help them feel their way in the dark. Each hair, and every feather, is attached to a network of nerves. When the hairs and feathers move, a message is sent to the nervous system, which translates and interprets that movement. In mammals and some birds, whiskers called vibrissae are sensitive feeling organs.

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Smell and Taste Your nose and mouth'are lined with cells Called chemoreceptors that are sensitive to the microscopic chemical molecules in smells and fQod. Your senses of smell and taste are very similar, but the receptors in your nose are 3,000 times more sensitive than the ones in 1 •• in~-:'tt1eY'~I~Jess} ..... ~9jlx: .Q1out~.! Food has to be in yo~r m?u~h for . and, especiany, the face. Cat' whiskers~' vi- "'you'to taste it. Your nose can detect fain,t brissae. Owls and goat suckers also have vismells from far away. brissae on their faces. Goatsuckers use their When your nose detects airborne molevibrissae to detect and scoop up insects. cules, it sends a message to your brain. Your They might also help protect the birds' eyes. brain then translates that message: '~a! Vibrissae are highly sensitive to air move- ,. Apple pie!" ment and may tell mammals when other aniMost insects and animals have far better mals are nearby. senses of smell and taste than you do. A salmon can return to the freshwater stream Antennae where it hatched by following the "smells" The antennae of insects are similar to vifound only in that stream. Many nocturnal brissae. They, too, are highly sensitive touch- mammals, such as deer, bears, rabbits, and ing organs. Not all antennae are located on badgers, not only have more powerful noses heads. Some insects and spiders have long than you do, but they leave scent trails to legs that act like antennae. Earthworms have mark their territories and to help them find their way. small antennae all over their bodies. CockSome animals produce scents from their roaches have two short spikes on the rear of glands, and to mark their territory, they rub their bellies that feel air movements. When the spikes detect motion, the cockroach betheir scent onto branches and rocks or leave their scent on the ground when they urinate gins to run away within 1/20 of a second! Many species, like crickets and spiders, or defecate. Male moths have enormous antennae that they use to detect the scent profeel and smell with their antennae. Snails duced by the female of their species. These smell with their antennae and the edges of antennae may have up to 1,700 tiny hairs that their feet. Snakes don't have antennae, but capture scent molecules, allowing the male to they flick out their tongues, scoop up chemical particles (smells), flick them into a special follow a female from a mile away.

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Smell and Feel Test Smell Set up a smell experiment with some friends. One person-the tester-goes into the kitchen, while everyone else stays out of sight in another room. Tester: take three common foods or substances, 'such as ketchup, a bar of soap, and jam (nothing too strong and nothing toxic!), and place them in three small bowls or cups ,on the counter. A fourth bowl should have nothing in it. Label the bowls one through four with slips of paper. Now blindfold the participants, one at a time, and bring them into the kitchen. Let each one smell the numbered bowls, then write down what they think they smelled on a pad of paper. What did they smell in the empty bowl?

Feel Close your eyes and have a friend gently blow the hairs on your ann or the back of your neck. Can you tell which way your friend is blowing? With a friend or two, take turns being blindfolded. Crawl around on your hands and knees outside and try to identify what you pick up, just by feel. (Your friends have to make sure you don't crawl somewhere unsafe.) Now, move indoors. Crawl around on a carpeted area. Take turns being blindfolded while your friend places objects on the carpet for you to find and describe. (Try objects such as an orange, a grapefruit, a small box, a dry sponge, a rock, a pen, or a sock.)