Good morning, class. It’s a beautiful spring day outside, isn’t it? We’ll soon be seeing the first robin of spring- and so, it’s a perfect day to begin talking about migration.

Migration is the main strategy that animals have for avoiding adverse environments and taking advantage of rich environments. Of course, there are other strategies, too- hibernation, for example- but far and away the most common way for animals to escape poor conditions and get to better ones is by migration- a mass journey from one place to the other.

Now there are all kinds of migrations, but the most familiar one is the sort that our robins will be experiencing- a seasonal, latitudinal migration. In the fall, the birds fly south, and in the spring they fly north again. In the southern hemisphere, of course, this works in the opposite direction. In both hemispheres, migrants move toward the equator when the earth chills and toward the poles when it warms. This is the way that species have been able to colonize, to use those subpolar resources that are seasonally difficult to access, that are unavailable to many living things for half the year.

Birds are certainly the most conspicuous latitudinal migrants, and they’re also the most awesome. Most famously, the Arctic Tern, which is a small seabird, migrates from one pole to the other, all the way from the Arctic subpolar region to the Antarctic subpolar region- and back again- annually. These birds travel roughly 70,000 kilometers a year!

In this topic the lecturer talks about animal migration, the causes why the animal migrate from one place to another and the reasons that animals experiencing seasonal changes. As he mention that animals also has strategies on how they live like escaping in poor environment, that they tend to flew on the south hemisphere during fall , and flew back to north during spring.because like human they are also sensitive to warm and cold season too. This is why birds migrates from one pole to the other and famously travel annually by 70,000 kilometers per year.