WARNING: This video includes death of characters and may be a little disturbing, especially for those of you who love birds.
I remember when I first heard about evolution, like many fundamentalists, I thought it sounded preposterous. Fish just decided to get out of the water and walk around? Didn't they just, you know--die as soon as they decided to do that? They sure did. By the gazillions. But, some of them managed to make it. And those ones were the ones who survived to breed. They had just a little more gumption or lung capacity, I suppose.
All it takes, is a new idea. And here, we see some fresh water catfish, discovering that there are tasty things to eat outside the water.
These catfish, as the eons progress and the birds who walk too close to the shore die out, will have to go further and further afield to eat pigeon. It won't seem like much of a leap each time. Just a little bit further for the taste they love (I hear pigeon tastes like chicken), but those who make the leap, might well develop the ability to process air in some fashion.
And the next thing you know...
If you have a very strong stomach and don't mind having your fuzzy ideas about how sweet animals are put to rest forever, I can recommend National Geographic's "Last Feast of the Crocodiles." It is a great video, in my opinion, because it has enough deception, suspense, tragedy and irony to rival anything by Shakespeare. But it is full of gore and horror and not for those with sensitive constitutions.
It illustrates, graphically, how life and death go hand in hand in this world. And, I think, to enjoy it, you have to move beyond judgment of predators and survivors. I've always had a certain sympathy for predators, because they don't win many of their battles. They may not be the best people (or critters) to have over for dinner, I grant you. But those with marked survival instincts are fascinating from a behavior standpoint, in my opinion.
Here's a link for the program on YouTube. Just the first little bit, the 2 minutes pre-credit, will give you a good sense of what I'm talking about...re: graphic entertainment.http://www.youtube.com/watch?v=DuyAsq4m2I0