Yes, I know I said a dirty word; geography, but believe it or not, geography is actually kind of useful in Science. And all I’m really asking for you guys to know is the name of most of the continents (there are 7) and the general shape.
Biogeography is the study of the distribution of plants and animals, both now and in the past (bio/biology = living things, geography = places). What you start to find (and this is evidence for both the theory of evolution and the theory of plate tectonics) is that along the borders of the continents, you find some very similar, if not the exact same, fossils.
Scientists used these similarities and came up with the idea that at some point in the Earth’s history, all the continents were joined together. Then they started to separate and become the landmasses that we know and love today.
This is all in the lead up to help explain this next idea. Scientists propose that, when the continents started to drift apart, there were living organisms! Shocking, I know. As the continents moved and the environments changed, it is suggested that the organisms adapted to better suit the environment. The example most commonly given is that of the flightless bird. We all know that the emu can’t fly. We all know the ostrich can’t fly. Now, hands up any of you who mixed these two birds up occasionally when you were younger?
Understandable, really. They’re both creepy, angry looking birds. I’m getting a bit paranoid one of them is watching me, just thinking about them.
Anyway, other flightless birds also include cassowaries, kiwis, rhea and penguins. Think about all of the countries that you would find these birds in. You can start to see why we might say that they all evolved from a common ancestor, right?
In summary, the next point in our evolution theory evidence stack is the similarity between species in vastly different environments.
Next topic up for discussion: The Amazing, Stupendous, PENTADACTYL LIMB!!
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