| Another fossil find was the Toxodon,
which was a rodent the size of an elephant -a rodent that lived mainly
in the water. It was like some vast, amazing cross between a rat and a
hippo. It was like a gargantuan capybara, the modern world's biggest rodent.
Gradually questions began to form in Darwin's mind. What was the
link between the fossil creatures and their smaller modern equivalents
that still lived in South America? Why had these huge creatures died out?
How had they died?
One conclusion that Darwin drew from his observations was that species
seemed to have changed over time, to have gained or lost certain characteristic
features. This was a disturbing conclusion, because it challenged the Biblical
idea that species were immutable, that they remained as God had made them.
The missing pieces only began to fall into place after Darwin visited the
Gallapagos Islands. These islands were inhabited mainly by reptile life
and by many different types of birds. |
