Question

for each statement, select the correct type of classification from the drop - down menu.
linnaean classification is based on the similar appearance of species.
cladistics is based on evolutionary relationships.
why are molecular clocks important in the construction of cladograms?
they compare the frequency of reproduction to determine which traits evolved through mutations.
they compare the genes inherited by a species to determine descendants.
they compare the number of mutations to determine how long ago species separated and evolved.

Explanation:

Molecular clocks work by comparing the number of mutations in DNA or protein sequences. The rate of mutation (assuming a relatively constant rate over time) allows scientists to estimate the time when two species diverged from a common ancestor. This time - estimation is crucial for constructing cladograms, which show evolutionary relationships.

• The first option about reproduction frequency is incorrect. Molecular clocks are not about reproduction frequency but about genetic changes (mutations).
• The second option about comparing genes to determine descendants is too vague. Molecular clocks specifically use the number of mutations (and the assumption of a molecular clock rate) to date evolutionary splits.

Answer:

They compare the number of mutations to determine how long ago species separated and evolved.