IN YOUR OWN WORDS: How do you perform a phylogenetic analysis of independent
contrasts? 1) You start with....... 2) Then you need....... etc. Last step: now we have values that
can be examined on a regression (where the line intersects the origin).
Solution
The phylogenetic analysis begun with assesment of character and character states and their
selection, the assesment of homology finally results in a sequential arrangement of character
states of the character which is known as a transformation series or morphocline. The
transformation series represent the hypothetical sequential arrangement of evolutionary change
from one character state to another in terms of direction and probability.
The similarity between the taxa can araise not only by common ancestry but also by independent
evolutionary origin. The similarity that is not the result of homology is known as homoplasy
(analogy).
Homoplasy may arise in two ways – by convergence and by reversal. Convergence is the
independent evolution of a similar feature in two are more lineages. For example, the
gamatophytic leaves of liverworts and sporophytic leaves of lycophytes evolved independatntly
as dorsiventral, photosythetic appendages. This similarity of leaves is set to be homoplasious by
convergent evolution.
The assessment of homoplasy or analogy by convergent evolution is carried out through
regression analysis when sufficient data is available and it is useful to measure degree of
divergence in related taxa that are evolved through convergent evolution..
IN YOUR OWN WORDS How do you perform a phylogenetic analysis of ind.pdf
1. IN YOUR OWN WORDS: How do you perform a phylogenetic analysis of independent
contrasts? 1) You start with....... 2) Then you need....... etc. Last step: now we have values that
can be examined on a regression (where the line intersects the origin).
Solution
The phylogenetic analysis begun with assesment of character and character states and their
selection, the assesment of homology finally results in a sequential arrangement of character
states of the character which is known as a transformation series or morphocline. The
transformation series represent the hypothetical sequential arrangement of evolutionary change
from one character state to another in terms of direction and probability.
The similarity between the taxa can araise not only by common ancestry but also by independent
evolutionary origin. The similarity that is not the result of homology is known as homoplasy
(analogy).
Homoplasy may arise in two ways – by convergence and by reversal. Convergence is the
independent evolution of a similar feature in two are more lineages. For example, the
gamatophytic leaves of liverworts and sporophytic leaves of lycophytes evolved independatntly
as dorsiventral, photosythetic appendages. This similarity of leaves is set to be homoplasious by
convergent evolution.
The assessment of homoplasy or analogy by convergent evolution is carried out through
regression analysis when sufficient data is available and it is useful to measure degree of
divergence in related taxa that are evolved through convergent evolution.
