Cladistics

Question 1

Taxon (plura taxa)

Answer 1

general term for any specific organism or groups of organism. For any classification level.

Question 2

Nodes

Answer 2

most recent common ancestor

Question 3

Primitive/Advanced

Answer 3

Primitive is older. Advanced is newer. Advanced does not mean they’re better. Bottom of tree is primitive, work your way up more advanced.

Question 4

Clade

Answer 4

group of taxa that consists of MCRA and all its decedents.

Question 5

Branch tips

Answer 5

Current living taxa. How branches attached at nodes matter. Not position at branches

Question 6

Outgroup

Answer 6

taxon/ most closely related of reference to clade of interest. Show most recent plesiomorphy.

Question 7

Homology

Answer 7

Homologs structures of character. Different taxa share same character due to inheritance from common ancestor.

Question 8

Homoplasy

Answer 8

Different taxa that have idependly acquired same characteristics, not through a common ancestor, (convergent evolution)

Question 9

Apomorphy

Answer 9

derived trait or characteristic that is unique to a taxon, but not found in ancestors. unique to a clade. implies homology.

Question 10

Monophyletic

Answer 10

MRCA and all its decendatnds, apomorphy

Question 10

paraphyletic

Answer 10

MRCA and some, but not all descendants. Plesiomorphic traits

Question 11

Synapomorphy

Answer 11

shared derived trait. derived trait that is shared by a group of organisms and their common ancestor.

Question 11

Plesiomorphy

Answer 11

ancestral trait or character that is shared by a group of organisms, including their ancestor

Question 12

polyphyletic

Answer 12

includes taxa, but not MRCA