A classic example of natural selection at work is the origin of giraffes’ long necks. The ancestors of modern giraffes were animals similar to deer or antelope, with necks of ordinary length.

Understanding this phenomenon allowed him to develop his concept of “natural selection” which, in turn, became a core element of his theory of evolution. Darwin observed that with such abundance, ...

Change can also occur by genetic drift or gene flow. What does ‘survival of the fittest’ mean? In terms of evolution, an animal that is ‘fit’ is one that’s adapted to its environment. This concept is ...

The proportion of well-adapted organisms in a population can increase over the generations by the process of evolution by natural selection.

So the question is, why? How could an animal be so precisely adapted to a particular lifestyle? The answer is natural selection. See, what must have happened, is way back when the ancestors of the ...

Edelaar, P. & Weissing, F. J. On the origin of species by natural and sexual selection. Science 326, 1704–1707 (2009). Via, S. Sympatric speciation in animals: The ugly duckling grows up.

In animals like the noolbenger/honey possum, females are highly promiscuous, forcing males to evolve some impressive anatomical changes. Charles Darwin's work in natural selection was pivotal to our ...

Aa Aa Aa Natural selection, genetic drift, and gene flow are the mechanisms that cause changes in allele frequencies over time. When one or more of these forces are acting in a population ...

Q: Tell us about this "dangerous idea" of Darwin's. A: I think Darwin's idea of natural selection is the best idea anybody ever had, ahead of Newton, ahead of Einstein. What it does is it promises ...