Jason M. Kamilar, Kathleen M. Muldoon
Niche conservatism relates a major theoretical concept in ecology, the niche, with a major theoretical concept of evolutionary biology, phylogeny. A measure of this is phylogenetic signal. This relates phylogeny to any traits so using it to measure environmental traits over a phylogeny gives a measure of niche conservation.
The paper looks at the relationship between the evolutionary distance between species and their ecological similarity for Malagasy primates. The idea is that for niche conservatism the relationship should be negative but in the case of an adaptive radiation there can be no relationship as the radiation usually occurs right after the species first arrives on the island. They concluded that there is no signal for this particular ecological data, i.e., climate. Although no phylogenetic signal was detected at the species level, some signal was detected at the family level although this is confounded by low power and by the fact that some genera are species poor.
The paper uses PCA (Principle Component Analysis) to orthogonalize the climate data and a new method (2) to determine the phytogenetic signal which gives a numerical statistic. The idea of niche conservatism (3) is that a close species should have close phenotypes and that this should show-up in ecological traits as well. For invasive species and island endemics this doesn’t seem the case (4). This could also be convergent evolution. One thing that I question in this is how does phenotype plasticity fit into all this? Microcebus (1) is quite plastic for climate so it might be the case for all Malagasy primates. It would be interesting to look at the closest ancestor in West Africa. Anolis sagrei are plastic in hind leg size and show the same loss of phylogenetic signal for climate, although a different method of determining this is used (4).
- Remarkable species diversity in Malagasy mouse lemurs (primates, Microcebus), A. D. Yoder et al.
- Testing for phylogenetic signal in comparative data: behavioral traits are more labile, S. P. Blomberg, T Garland, Jr., and A. R. Ives
- Niche conservatism above the species level, E. A. Hadly, P. A. Spaeth, and Cheng Li
- Phylogenetic analysis of the evolution of the niche and of species associations in lizards of the Anolis sagrei group, J. H. Knouf et al.