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So what's up? What kinds of animals will Jacob find in his backyard?

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Will the treehouse detectives find a new species?

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Is a backyard nature preserve a good idea?

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Find out in the next exciting chapter of The Case of the Zany Animal Antics.

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Be sure to look for the answers to the following questions.

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What are the basic needs of animals?

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What are the three basic reasons animals migrate?

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What is different between mitosis and meiosis?

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Why is it important for a species to have genetic diversity?

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You're not going to believe it, but it's all right here.

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With proper planning and maintenance, you can create your own backyard preserve or habitat.

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That's amazing.

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And if you follow their guidelines, you can actually have your backyard officially recognized.

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How'd you find out about all this?

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I have a friend who deals strictly with agricultural stocks.

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I gave him a few leads on some farm equipment companies, and he gave me the scoop on backyard habitats.

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Cool.

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So is everybody helping out?

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All the treehouse detectives are pitching in.

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Catherine and Bianca are down at NASA Kennedy in Florida,

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and RJ is at Adventure Camp at Bush Gardens in Tampa.

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You certainly have a great team.

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Well, we haven't officially heard from RJ yet, but Dr. D is going to talk to him down in Florida.

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And of course, NASA is a big resource.

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Yes, they are.

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In fact, Catherine and Bianca are supposed to talk to Mr. Mario Mota there today.

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I hope they remember to download their get-up-and-go sheets.

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You can download your own get-up-and-go sheet at the NASA SciFiles website.

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Ms. Smith was right.

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Mr. Mario Mota agreed to meet with us about animals.

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He's a wildlife biologist working with sea turtles here at NASA Kennedy Space Center.

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We hope to learn more about basic needs of animals,

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and if we're lucky, we may find a sea turtle nest on the beach.

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Well, an animal's basic needs are pretty simple.

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They need food, water, shelter, and another mate so they can reproduce.

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That sounds simple enough.

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But how do you know what kind of food animals need?

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It depends on the species, but no matter what kind of animal it is,

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you've got to make sure you have a healthy food chain.

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Do you know about the food chain?

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We've studied the food chain in school.

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It's the process of energy being transferred from one organism to another.

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That's right. All living things need food for energy.

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Producers such as plants, algae, and other organisms

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convert light energy into sugar molecules that the plant uses for food energy.

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A portion of this energy is passed on when animals called consumers eat the plants.

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And then other consumers eat the consumers that ate the plants.

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Very good.

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And then energy stored in the molecules of one organism is transferred to another organism.

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Making a food chain.

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Plants are at the bottom.

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Animals such as deer and rabbits are called herbivores and they eat the plants.

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The herbivores are then eaten by a carnivore such as a wolf or lion.

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Aren't there some that eat both plants and animals?

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Yes, they're called omnivores.

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In the final stage of the food chain, when an animal or plant dies,

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they're broken down by bacteria called decomposers.

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Decomposers turn the remains into materials that can be used by the plants.

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The food chain seems simple at first, but they're really complex.

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In a habitat, there are many feeding relationships.

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Some can be very complex, so scientists use a food web to better share these relationships.

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A web like a spider's web?

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Actually, a spider's web is a good analogy.

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It is intricately woven and connected just like a food web.

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What if something happened to an animal's habitat?

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The food web would be disrupted

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and it could disrupt the balance of plant and animal populations.

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What do you mean?

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Let's say a fire destroyed a habitat and removed all the plants.

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Without plants, then the herbivores would not have food to eat.

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Without herbivores, then the carnivores would also starve.

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The animals would have to move to a new habitat.

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It's not always that easy.

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Some habitats are small or enclosed by human development such as subdivisions,

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making it difficult for animals to migrate to a new habitat.

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If they can't find a new habitat, won't they die?

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They might, and it could even lead to the extinction of some species.

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I never realized that everything is so connected.

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Yes, it is, and as part of my job here at NASA,

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I study the sea turtles that live in the estuaries and lagoons

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to make sure that their habitats aren't disrupted.

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Mr. Mota told us all about how sea turtles are endangered and threatened

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and how the beaches of NASA Kennedy provide nesting sites for them.

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By monitoring their population health, age structure, growth reproduction,

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mortality, and the impact of human activity, NASA can help the species thrive.

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We didn't get to see any, but Mr. Mota said that to do that,

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we would have to go out to sea.

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I never knew that working as a zookeeper required so much.

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Feeding, raking, cleaning, more feeding.

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It's hard work, but it's very rewarding.

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Of course, I'm looking forward to my break.

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Hopefully, I can take care of a little research for the treehouse detectives

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when I meet Dr. D today.

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I'm the Busch Gardens Serengeti Plain habitat.

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Each zebra has a unique set of stripes,

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which creates an optical illusion that confuses a predator.

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Oh, and I also learned that in 12 months,

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the animals of the Serengeti Plain in Africa

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will travel in a large circle of about 1,000 kilometers.

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That's right.

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The migration includes hundreds of thousands of herbivores,

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including Thompson's gazelles, zebras, and wildebeest like these here.

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Wow, they're pretty funny-looking animals.

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African legend says they're made for spare parts.

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Wildebeest are, however, well-suited for their migration.

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For example, most wildebeest calves can stand and run

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in less than 10 minutes after birth.

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Wow, that's amazing.

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But I thought migration meant going south for the winter.

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Does it get that cold in Africa?

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No, but there are seasons, wet and dry.

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During the dry season, the grass dries out and water becomes scarce.

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The herbivores that migrate leave in search of new grass and plentiful water.

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I know that other animals, like birds, will migrate great distances.

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Is this also in search of food?

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There are three basic reasons for migration.

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The first is food and water.

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The second is to escape harsh weather.

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So I guess that when birds fly south for the winter,

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they get both a milder climate and more food.

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Very good.

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When they go north for the summer,

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they get more hours of daylight to gather food.

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How do animals travel thousands of kilometers to find their destination?

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They must have some way to navigate.

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Are you ready to try an experiment?

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Okay, why not?

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Close your eyes and I'll spin you around.

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Now, keep your eyes closed and point north.

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Are you kidding, Dr. D?

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I can't point north with my eyes closed.

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I'm not even sure if I can point north with my eyes open without a compass.

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Some animals can.

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They have a built-in compass in their head that helps them find their destination.

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Other animals use the sun or stars to find their way.

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Do other animals just use landmarks such as mountains or lakes on their journeys?

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Sometimes they do.

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Salmon migrate using a keen sense of smell.

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Dr. D, can I ask just one more quick question?

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Sure, RJ.

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Can I open my eyes now?

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Of course.

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You'll need to see to feed the giraffes.

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Dr. D, didn't you say there are three reasons for migration?

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Good memory, RJ.

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The third reason for animal migration is reproduction.

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They want to provide their young with plenty of food

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and with protection from predators and extremes in the environment.

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I should have guessed reproduction.

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That's one of an animal's basic needs.

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And migration is all about meeting basic needs.

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Thanks, Dr. D.

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I'm working at the Nairobi field station later today.

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That would be a great place to learn more about animal reproduction.

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Right.

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But first, let's get some more hibiscus leaves for the giraffe.

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I've been going over our notes so far,

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and I thank Jacobson for a big surprise.

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There's a lot to consider when it comes to creating your own preserve.

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Right.

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Like whether your property is rural, suburban, or urban,

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and what types of wildlife the habitat will support.

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And, of course, you have to support the basic needs of the animals in your habitat.

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Otherwise, they might migrate to another area.

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Good thing we have RJ's notes on migration.

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And Dr. D. talked about animal growth through reproduction.

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Which is critical to the population.

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Hopefully, RJ will learn more at the Nairobi field station at Bush Gardens in Tampa.

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He's working with Ms. Deidre as we speak.

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We should visit Jacob's backyard to see what types of animals already live there.

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Good idea.

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Otherwise, I'll have to hire some survey consultants as well.

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What do you mean?

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Well, if the habitat is successful,

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I have other problems to consider.

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Parking, ticket prices, a possible trios detective gift shop.

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I'm sure you'll be giving Jacob some of the proceeds.

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Don't worry. He's salaried.

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Dr. D. mentioned that animal reproduction was important for the survival of species.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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I know.

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This actually contains DNA.

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Now DNA is a genetic code that determines the characteristics of animals, such as blonde hair, or brown hair

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or blue eyes or green eyes. And so on as with humans.

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So how does cells reproduce?

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All cells reproduce from other cells.

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Do all cells reproduce the same way?

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No, there are actually two ways that cells reproduce.

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One way that cells, such as body cells reproduce is through mitosis.

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In mitosis, the cell duplicates its genetic material and then splits in two, forming two identical cells.

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Mitosis is the process by which animals are able to grow.

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Okay, so if that's mitosis, what's the other way?

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Meiosis.

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In this method, certain cells in the reproductive tissue divide so that they contain exactly half of the genetic material.

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The chromosomes that carry the genetic codes occur in pairs.

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And during meiosis, one half of each pair goes to the new cells.

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In males, these are the sperm cells.

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And in females, they're the egg cells.

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Okay, so what does cell division have to do with reproduction?

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In asexual reproduction, an offspring is formed from one parent cell.

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The parent cell goes through mitosis and forms an offspring that is identical to the parent.

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What types of animals reproduce asexually?

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Flatworms and sponges are two of them.

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Starfish, also known as sea stars, reproduce by regeneration, which is a form of asexual reproduction.

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Right.

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My dad said that if a starfish loses one of its rays, then it'll grow a new one.

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And the one that broke off will grow four more.

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That's right.

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Long ago, some fishermen had a problem with starfish getting caught in their nets.

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So they tried to get rid of them by chopping them into pieces.

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But they were actually only adding to the problem because each new piece grew new limbs and created more starfish.

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It sounds like they could have used a scientific method and done more research before they tried to solve the problem.

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So what is sexual reproduction?

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Well, it occurs when a sperm and egg cell combine to produce a new cell, which is called a zygote, which will then grow into an offspring.

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Now, the offspring produced will receive a combination of genetic material from both the male and female parent.

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Is one type of reproduction better than the other?

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No, it just depends on the animal.

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However, with sexual reproduction, meiosis helps to sort of shuffle the genetic material to the offspring to help ensure genetic diversity.

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Why is that important?

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Well, genetic diversity is critical for a species' survival because it increases the probability that only healthy, strong individuals will be produced.

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Additionally, genetic diversity also helps reduce the probability that a genetic defect will overcome a population.

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So would it be important to have a large population of a species for better genetic shuffling?

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Yes. With a large population, there's much more genetic diversity.

249
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Are there any factors that keep animals from reproducing?

250
00:12:43,160 --> 00:12:49,160
Sure there are. Geographic isolation, genetic defects, and a lack of food, water, and shelter.

251
00:12:49,160 --> 00:12:53,160
So for reproduction, it's pretty important to make sure that an animal's basic needs are met.

252
00:12:53,160 --> 00:13:02,160
Yes, it is. Without adequate amounts of food, water, and shelter, animals will actually stop reproducing so that they can better enable those that are living to survive.

253
00:13:02,160 --> 00:13:05,160
I can't wait to send my report to the treehouse detectives.

254
00:13:05,160 --> 00:13:08,160
Maybe you can email them after we clean the porcupine habitat.

255
00:13:08,160 --> 00:13:11,160
Well, a zookeeper's job is never done.