What was the name of the ship Darwin traveled on?

In a population of forest voles the ratio of brown furred animals to white furred animals is 50/50. After a forest fire, the ratio is found to be 75/25. This is an example of

Two groups of squirrels reside on two spatially separated islands in the St Lawrence river therefore they belong to the same population.

What is an example of a reproductive barrier

Darwin wrote the book "On the Origin of Species" years after he explored the Galapagos and made his observations. In it, he introduced the concept of

Sexual selection cannot lead to changes in a gene pool over successive generations.

Which of the following are components of natural selection?

In addition to natural selection, what else can contribute to gene pool evolution

Phylogenetic trees are one way to reflect the evolutionary history of organisms.

The biosphere does not include abiotic factors