On his major journey on the Beagle, Darwin discovered many interesting facts like a bird that was a mixture of lark, pigeon and snipe, or races that were barbarian walking around naked with temporary houses that normal children would build in the summer out of boughs of trees (Barret vol.1 6). ... In Argentina, he found 23 species of shells, some of which had been extinct, and the Bible had no explanation for either of these facts. ... These differences would vary from island to island which means that when those birds arrived at the islands they had to adapt and change or they would perish ...

• Word Count: 1915
• Approx Pages: 8
• Has Bibliography

These variations are minor and they do not occur so frequently as to threaten the survival of the species as a whole, but these variations are entirely random, and thus they do not always work to the benefit of the organism. ... For example, a hawk exhibits certain behaviors when it sees a flock of birds. The hawk has an instinctual, biological drive that has been triggered to go out and look for food, but it hasn't consciously realized that a flock of birds could denote prey. ...

• Word Count: 2370
• Approx Pages: 9
• Grade Level: Undergraduate