For the present study, monophyletic pairs of sister lineages that display differences in current species-richness were chosen from Sauquet et al's phylogeny.
Such structures may have little or no function in a current species, yet have a clear function in ancestral species, or other closely related species.
A central debate in Neotropical biogeography concerns the importance of Pleistocene climatic and geological events in generating current species richness [ 1- 4].
It is likely that the wide physiological tolerance to the array of conditions encountered in the current species range, finally also limits the distribution of R. balthica.
After the whole-genome duplication in the common ancestor of salmonid fish, its karyotype would have ∼100 chromosome arms, which is the number found in all current species of the Pacific salmon and trout (genus Oncorhynchus).
Other management options being considered in the current species recovery planning process include reducing illegal fishing, reducing disease risk, establishing new populations, increasing community awareness and establishing a long-term monitoring programme (I&I NSW, 2010).
As shown in figure 2A D, there are 40 chitinase genes, 19 β-1,3/1,6-glucanase genes, 27 cellulolytic enzyme genes, and 24 hemicellulolytic enzyme genes in the most recent common ancestor (MRCA) of the four Trichoderma species, all of which are more than those in the current species.
Furthermore, given the limited size of the available collection of sequenced genomes, what appears to be emergence of a gene in an ancestral form could be the result of HGT from a lineage that is not represented in the current species tree.
