CONFOUNDING ASYMMETRIES IN EVOLUTIONARY DIVERSIFICATION AND CHARACTER CHANGE

Asymmetries in phylogenetic diversification and character change can be untangled.

The analysis of diversification and character evolution using phylogenetic data attracts increasing interest from biologists. Recent statistical developments have resulted in a variety of tools for the inference of macroevolutionary processes in a phylogenetic context. In a recent paper Maddison (2006 Evolution, 60: 1743-1746) pointed out that uncareful use of some of these tools could lead to ...

Evolutionary patterns in early tetrapods. I. Rapid initial diversification followed by decrease in rates of character change.

Although numerous studies have examined morphological diversification during major radiations of marine taxa, much less attention has been paid to terrestrial radiations. Here, we examine rates of character change over phylogeny and over time for Palaeozoic limbed tetrapods. Palaeozoic tetrapods show significant decreases in rates of character change whether the rate is measured per sampled cla...

Evolutionary diversification in polyamine biosynthesis.

Polyamine biosynthesis is an ancient metabolic pathway present in all organisms. Aminopropyltransferases are key enzymes that mediate the synthesis of spermidine, spermine, and thermospermine. The relatively high sequence similarity between aminopropyltransferases and their similarity with putrescine N-methyltransferases (PMT) raises the question of whether they share a common ancestor or have ...

Competitive and Facilitative Evolutionary Diversification

C estimates place the number of named species at about 1.4 million (WRI 2001). Scientists continue to discover new species daily, and estimates suggest the total number of species on Earth is somewhere between 2 million and 100 million. More remarkable is that over the past 3 billion to 4 billion years, this enormous diversity of living creatures appears to have evolved from very few ancestral ...

Brain Size and Evolutionary Diversification in Birds