Question 1

What is natural selection and how does it contribute to evolution?

Accepted Answer

Natural selection is a process where organisms with traits better suited to their environment tend to survive and reproduce more than those with less advantageous traits. Over time, this leads to changes in the traits of populations, contributing to evolution. In the context of IB DP Biology, understanding natural selection helps explain how species adapt and evolve over generations, influencing biodiversity.

Question 2

How does natural selection differ from artificial selection?

Accepted Answer

Natural selection is an unguided process driven by environmental pressures, where advantageous traits increase an organism's chances of survival and reproduction. In contrast, artificial selection is a human-driven process where specific traits are chosen for breeding, such as in agriculture or animal breeding. Both processes result in changes in species over time, but natural selection is a key mechanism of evolution in the wild, as studied in IB DP Biology.

Question 3

Can you provide an example of natural selection in action?

Accepted Answer

A classic example of natural selection is the peppered moth in England. Before the Industrial Revolution, light-colored moths were more common because they blended in with the lichen-covered trees, avoiding predation. However, as pollution killed the lichens and darkened the trees, dark-colored moths became more common because they were better camouflaged. This shift in population demonstrates natural selection, a key concept in the Evolution and Biodiversity unit of IB DP Biology.

Question 4

What role do mutations play in natural selection?

Accepted Answer

Mutations introduce genetic variation, which is essential for natural selection. While most mutations are neutral or harmful, some can provide advantageous traits that improve an organism's fitness in a given environment. These beneficial mutations can be passed on to future generations, contributing to evolutionary change. In IB DP Biology, understanding the role of mutations helps explain how genetic diversity fuels natural selection and evolution.

Question 5

How does natural selection lead to speciation?

Accepted Answer

Natural selection can lead to speciation when populations of a species become isolated and adapt to different environments over time. As these populations accumulate genetic differences, they may become reproductively isolated, forming new species. This process is a fundamental aspect of evolution and biodiversity, and is a key topic in the IB DP Biology curriculum, illustrating how diversity in life forms arises through evolutionary mechanisms.

Natural selection

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