Knowing phylogenetic relationships among species is fundamental for many studies in
biology. An accurate phylogenetic tree underpins our understanding of the major transitions …

A classification of the entire Phylum Nematoda is presented, based on current molecular,
developmental and morphological evidence. The classification reflects the evolutionary …

Proteins have distinct structural and functional constraints at different sites that lead to site-
specific preferences for particular amino acid residues as the sequences evolve …

The evolutionary relationships of two animal phyla, Ctenophora and Xenacoelomorpha,
have proved highly contentious. Ctenophora have been proposed as the most distant …

How animals evolved from a single-celled ancestor, transitioning from a unicellular lifestyle
to a coordinated multicellular entity, remains a fascinating question. Key events in this …

The world's most revered and eloquent interpreter of evolutionary ideas offers here a work of
explanatory force unprecedented in our time—a landmark publication, both for its historical …

Gene duplication has generally been viewed as a necessary source of material for the origin
of evolutionary novelties, but it is unclear how often gene duplicates arise and how …

Two small RNAs regulate the timing of Caenorhabditis elegans development,. Transition
from the first to the second larval stage fates requires the 22-nucleotide lin-4 RNA,,, and …

The first two known microRNAs (miRNAs), lin-4 and let-7, were originally discovered in the
nematode Caenorhabditis elegans and control the timing of stem-cell division and …

Nematodes are important: parasitic nematodes threaten the health of plants, animals and
humans on a global scale,; interstitial nematodes pervade sediment and soil ecosystems in …