What Would You Find at the Root of a Phylogenetic

question 129

Multiple Choice

What would you find at the root of a phylogenetic tree?

• A) All living species
• B) Some living species and some dead species
• C) The common ancestor of some, but not all, of the species depicted in the tree
• D) The common ancestor of all species depicted in the tree
• E) Synapomorphies

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Definitions:

White Sharks

A species of large, predatory fish known scientifically as Carcharodon carcharias, commonly referred to as the great white shark.

Troposphere

is the lowest layer of the Earth's atmosphere, where nearly all weather conditions take place, and temperature generally decreases with altitude.

CO₂

Carbon dioxide, a colorless, odorless gas produced by burning carbon and organic compounds and by respiration. It is naturally present in air and is absorbed by plants in photosynthesis.

UV Radiation

Ultraviolet radiation is a form of electromagnetic radiation that comes from the sun and man-made sources like tanning beds, capable of causing skin damage, including sunburn and skin cancer.