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1 .Listen to part of a lecture in a biology class.
1 .For today's discussion, we'll review the case study on how some animals have behaviorally adapted to their environments.
2 .Now you had to read about two animal species, the Eastern marmot and the Olympic marmot.
3 .Marmots are rodents.
4 .They are large ground squirrels, about the size of an average house cat.
5 .And they live in a variety of habitats.
6 .And even though they spend the significant portion of the year hibernating, according to this case study, marmots are still considered excellent subjects for animal behavioral studies.
7 .Why is that?
1 .Well, when they are not hibernating, you can find them in open areas.
2 .And they are pretty active during the day, which makes them easy to observe, right?
1 .Uh-huh, so first let's discuss the Eastern marmots.
2 .They reside throughout the eastern region of North America where there is a temperate climate, where the growing season lasts for at least five months of the year, which is when they do all their mating, playing and eating.
1 .Oh, I see. At first I wasn't sure what growing season meant, just from the reading.
2 .But now I get it.
3 .It's the amount of time it takes for them to grow, right?
4 .So it would be five months?
1 .Umm? Oh, uh... I'm sorry but no.
2 .It has nothing to do with that.
3 .It's not about the time it takes for Eastern marmots to grow.
4 .It's when the food is available.
5 .That is when it's not covered in snow and there is no frost covering the grass and umm, vegetative parts of a plant's herbs and the flowers the marmots like to eat.
6 .So growing season refers to the availability of the food they eat, OK?
7 .So now how would you describe the Eastern marmots' social habits?
1 .Well, they are really territorial, and loners, and just so aggressive even with other Eastern marmots.
2 .And their mating ritual is just so impersonal.
2 .Now when they emerge in the spring from hibernation, the mating process begins.
3 .For them, well, they come together to mate and then they go their separate ways.
4 .Then about six to eight weeks after birth, the offspring leave their mothers.
1 .Really? Just six weeks?
2 .Is that possible for the offspring to make it on their own so young?
1 .Well, it's not as if they aren't ready for the real world because they are.
2 .Remember, they mature quickly and the weather's nice.
3 .Also they live in open fields where there is lots of edible vegetation.
4 .So roughly six weeks after birth,
5 .Eastern marmots are just old enough to take their chances of surviving in the temperate environment.
6 .So how does this relate to their behavior?
1 .Oh, I get it.
2 .Since the climate's not too bad, the Eastern marmots don't have to rely on each other too much and they really don't need to stay together as a family to survive either.
1 .Uh-huh. Any contrast, the Olympic marmots? What about them?
1 .Well, they live together as a family and take care of their young until they are at least two years old.
2 .They're really friendly with each other.
3 .And what I really like is that they even have greeting ceremonies.
4 .And they are not at all aggressive and territorial like the Eastern marmots.
5 .So their social behavior is so different from Eastern marmots because of the climate where they live?
6 .That seems so bizarre.
1 .Well, the Olympic marmots inhabit meadows high in the Olympic Mountains where the weather conditions are much harsher.
2 .So there is a lot more wind and snow.
3 .The growing season only lasts about two to three months.
4 .So in that much shorter period of time, all the Olympic marmots, male and female, eat, play, work and nurture the young together.
5 .Because the climate is so harsh, cooperation increases the survival rate of the Olympic marmots.
6 .They keep their young at home until they are physically able to survive on their own.
7 .This could explain why the social behavior of the Olympic marmots is so unlike that of the Eastern marmots.