Question

unit exam - darwins theory of evolution
what is a clade?
all species with the same homologous trait
when a new species splits off from its current one
the end groups on an evolutionary tree
a group of organisms with one common ancestor and all its descendants in an unbroken line

Explanation:

A clade is defined as a group of organisms that share a common ancestor and include all descendants of that ancestor. This concept is fundamental in cladistics, a method of classifying organisms based on evolutionary relationships. The first option ("all species with the same homologous trait") is incorrect because homologous traits can be present in multiple clades. The second option ("when a new species splits off from its current one") describes speciation, not a clade. The third option ("the end groups on an evolutionary tree") is too vague as end - groups can be part of different clades. The fourth option accurately captures the definition of a clade by emphasizing the common ancestor and all its descendants in an unbroken line.

Answer:

a group of organisms with one common ancestor and all its descendants in an unbroken line