an inordinate fondness for eukaryotic diversity的对真核生物的多样性.pdfVIP

Primer An Inordinate Fondness for Eukaryotic Diversity Luke J. Harmon* Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America clade of lizard-like reptiles that currently inhabit small islands Abstract: Why do some groups of organisms, like around New Zealand (Figure 1, left). These tuatara are the sister beetles, have so many species, and others, like the clade to the squamates, a clade of 7,000 species that includes all tuataras, so few? This classic question in evolutionary living snakes and lizards (Figure 1, right) [2]. Since these two biology has a deep history and has been studied using groups are sister clades, they diverged from a common ancestor at both fossils and phylogenetic trees. Phylogeny-based exactly the same time (,250 million years ago [3]). Tuataras used studies have focused on tree balance, which compares to be far more diverse in the past (though almost certainly not as the number of species across clades of the same age in diverse as squamates [4]), but their current diversity is dwarfed by the tree. These studies have suggested that rates of the tremendous number and variety of snakes and lizards around speciation and extinction vary tremendously across the the globe. Similar patterns occur across the whole tree of lif