Comparing Spider Communities Level 3

Level 3: Identifying the evolutionary relationships between the different spider species. This is also important when it comes to decision-making because if one ecosystem has evolutionarily unique specimens, this might be the ecosystem that is most important to protect.

When contrasting patterns of species diversity and community distinctiveness, we typically treat each species as equally important, yet are they? What if a species-poor area actually is quite evolutionarily distinct from others? Should this be protected over the highly diverse ecosystem which contains a swarm of species that have only recently diverged from one another and are quite similar to species present at another site?

In this third level of classification, scientists determine whether there is any evolutionary link between the spiders by grouping spiders according to similar traits. The best way to determine whether two spiders are related is to compare the genes of the two species.

Based on the evolutionary relationships that exist among the spiders, scientists can prioritize forest patches for protection based, in part, on patterns of species diversity at the genetic level.


Source: http://cnx.org/content/m12179/latest/ (CC BY)