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A modern goal of systematics is to classify organisms based on physical appearances, not common ancestry.

Alan Cooper, Cécile Mourer Chauviré, Geoffrey Chambers, Arndt von Haeseler, Allan Wilson and Svante Pääbo investigated the evolutionary relationships among some extinct and living species of flightless birds. They concluded that kiwis are more closely related to African and Australian flightless birds than they are to the moas. What new hypothesis did they propose based on this conclusion?

Which pair of species would be expected to have more genetic differences: orangutans and gorillas or gorillas and humans? Why?

When comparing the sequences of a homologous gene in four different species, one pair of species shows a 20% difference, whereas the other pair shows a 15% difference. Which pair diverged longer ago from their common ancestor and why?

The octopus (Octopus vulgaris) and the zebra mussel (Dreissena polymorpha) are both members of the phylum Mollusca.  This indicates that they must also both be members of the same

What is the source of carbon for the synthesis of organic molecules in a photoautotroph or any autotroph in general?  

Molecular clocks are usually calibrated based on  

Cladograms include in the phylogenetic tree shared primitive characters and shared derived characters. The derived characters can also be called ______ while the primitive characters can also be called __________.  

When one species consisting of a single large population slowly evolves over many generations into several populations of a several new species, this is an example of 

Fortunately, it is possible to obtain DNA from small tissue samples of extinct species for use in constructing phylogenetic trees.