Sedimentary organic matter derives from biological precursor material which undergoes
systematic, irreversible changes upon burial which mainly reflect increasing diagenetic …

Deuterostomes are the major division of animal life which includes sea stars, acorn worms,
and humans, among a wide variety of ecologically and morphologically disparate taxa …

This book presents a comprehensive overview of the science of the history of life.
Paleobiologists bring many analytical tools to bear in interpreting the fossil record and the …

Summary Ambulacraria, comprising Hemichordata and Echinodermata [1], is closely related
to Chordata, making it integral to understanding chordate origins and polarizing chordate …

Abstract The Ordovician of Scandinavia (ie Denmark, Norway and Sweden) has been
investigated for over two centuries and, through time, various chronostratigraphic schemes …

Evidence of interspecific interactions in the fossil record is rare but offers valuable insights
into ancient ecologies. Exceptional fossiliferous sites can preserve complex ecological …

Background The combination of a meager fossil record of vermiform enteropneusts and their
disparity with the tubicolous pterobranchs renders early hemichordate evolution conjectural …

Hemichordates are a marine group that, apart from one monospecific pelagic larval form, are
represented by the vermiform enteropneusts and minute colonial tube-dwelling …

The diversity of regenerative phenomena seen in adult metazoans, as well as their
underlying mechanistic bases, are still far from being comprehensively understood …

Re-evaluation of eumetazoan modular coloniality gives a new perspective to Ediacaran–
Ordovician animal diversification. Highly integrated eumetazoan colonies (porpitids …