Whales, Chimps, and Sex, OH MY!

One of my favorite topics in teaching about evolution is that of the history of whales. It is probably one of the most intriguing transformations in the history of life on Earth, one that facinating to think about and study. Recently I have had dreams about whales; dreams with powerful imagery of these awe-inspiring animals. I won't conjecture as to the meaning behind them, but anytime a theme or symbol recurrs in our dreams I would say that it makes us take notice.

Whales, as with all living things, are products of evolutionary processes. Evolution, at its very core, relies on the fact that nature is not "nice." Some individuals, inevitably, have to die in order for natural selection to occur. Sea World has been lying for years, as you can see in the following:

By our standards, many of these deaths are cruel; gruesome. Have you seen the preview for the Disney Nature movie about the Big Cats?

When I first saw this, I leaned over to Jerre and asked, "Do you think they're going to show the part where the male lions kill the cubs that aren't his?" Infanticide often occurs in nature. Lions kill the cubs after taking over a pride that once belonged to another male. Chimpanzee infants are killed by adult males- so often that females try to mate with every male in the group. The logic? If the child may be his, maybe he won't kill it. Our closest relatives have some seriously violent tendencies. Hmm.

Some of the reason behind this? Males reach food sources sooner than females who are slowed down by their young. It is hypothesized that shortage of food forces chimpanzee females to spread out and forage alone, thus inhibiting female bonding. Bonobos, on the other hand, have a much more peaceful society due to an evolutionary history that includes more plentiful food sources. If you haven't watched "Why Sex?" then you're seriously missing out. These powerful forces of nature have not only determined our physical characterisics, but also many of our behavioral characteristics as well. Here is a segment from "Why Sex?" and, if you are interested, the other segments can be viewed via YouTube.  

  

Intriguing science, I must say. We don't, on an everyday basis, think about our origins in the grand scheme of things. Perhaps we should. My students were shocked to learn that they share about 60% of their genes with a banana (well, the tree that produces bananas if you want to get technical about it.) This knowledge of our own existance is what makes us human. We alone, have the ability to reflect on our own origins and conjecture as to our future. A powerful thought.  

Teaching is a profession that revolves around the content that one teaches. Spring is time for evolution. Go forth, and evolve.


Other Articles/Links of interest:

PBS whale evolution video and synopsis
http://www.pbs.org/wgbh/evolution/library/03/4/l_034_05.html


National Geographic Article: Valley of the Whales
http://ngm.nationalgeographic.com/2010/08/whale-evolution/mueller-text