Listen to part of a lecture in a biology class.
(female professor) Many animals live underground, in the soil. Not just little animals like worms but also bigger animals like mammals. Living underground has its advantages. It protects animals from above ground predators. However, the underground environment also presents challenges. And animals that live underground have developed physical adaptations to deal with them. One challenge is, well, simply how to move underground through the dirt. Another challenge for the animal is to protect vulnerable parts of its body from the environment that it's moving through.Now, moving through soil is not like moving through air or water, because soil, earth, is thick and dense, so animals that live underground have evolved physical features that help them move through dirt efficiently. For example, the mole, a small, furry mammal, has really wide, super strong front feet with big claws. The mole's feet act like, uh, like shuffles, so it can dig through dirt. The claws cut into the dirt, loosen it up, and once the dirt is loosened up, the broad feet throw the dirt behind the mole as it moves forward. These shuffle-like front feet allow a mole to dig its way through the dirt astonishingly quickly. But even for an animal that can move efficiently through the dirt, living underground can still be problematic, because it’s easy for particles to get caught in sensitive parts of the animal’s body, like for mammals, in their eyes, so underground animals have developed adaptations to prevent this. Again, let’s take the example of the mole. To begin with, moles have tin y eyes and these eyes are covered with a thin skin, a protective membrane that’s actually got hair on it. These hairs protect the mole’s eyes from dirt particles. So as the mole goes digging through the dirt with its head push forward, the dirt particles come into contact with the hairy membrane covering the mole’s tiny eyes. And the particles just slide by. Don’t get caught in the mole’s eyes. So the eyes, the mole’s sensitive parts, are protected.
Using the example of the mole, explain two different types of underground adaptation.
One challenge for underground animals to live underground is to move underground through dense and thick soil. And these animals develop certain adaptations to solve the problem. For example, mole, a small furry mammal has wide and strong front feet with claws so that when it moves forward, the claws dig into the dirt, loosen the soil and its broad feet will throw the soil behind. In this way it can move through the hard soil very quickly. Another challenge is to protect the vulnerable parts of their body while moving under the soil. Back to the mole, besides the claws, it develops hairy membrane on their tiny eyes. When the dirt and particles come into contacts with the membrane while the mole is moving forward in the dirt, they just slide by rather than get caught in the mole's eyes. In this way the mole manages to protect its sensitive eyes from the soil and particles. (157 words)
