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How does understanding biology help us classify organisms?Evolutionary trees

Advances in biological techniques have had a huge impact on the way that scientists classify organisms on Earth. They have helped us to find out to what extent organisms are related to one another.

Part of Biology (Single Science)Life on Earth - Past, present and future

Evolutionary trees

Evolutionary trees are used to represent the relationships between organisms. Branches show places where has occurred, and a new species has evolved.

Evolutionary trees are a method used by scientists to represent the relationships between a set of organisms.
Figure caption,
An evolutionary tree

In this evolutionary tree, species A and B share a recent common ancestor. Species A is therefore most similar to species B.

Species F and G also share a recent, common ancestor, however this common ancestor is different to the common ancestor of A and B. The common ancestor of F and G shared a common ancestor with species E. All seven species share a common ancestor at the bottom of the tree, probably from the distant past.

The information is collected from a variety of sources such as fossil records and DNA sequences. The more varied the collected, the more likely the scientists are to be correct in their decisions about how closely related different organisms are.

Question

In the evolutionary tree above, which two species were formed by only two speciation events?

Question

In the evolutionary tree above, which species is likely to look most like species C?