Fossil Abundance and Community Stasis

The relative importance of directional change, random walks, and stasis in the evolution of fossil lineages.

The nature of evolutionary changes recorded by the fossil record has long been controversial, with particular disagreement concerning the relative frequency of gradual change versus stasis within lineages. Here, I present a large-scale, statistical survey of evolutionary mode in fossil lineages. Over 250 sequences of evolving traits were fit by using maximum likelihood to three evolutionary mod...

LONG - TERM STASIS IN ECOLOGICAL ASSEMBLAGES : Evidence from the Fossil Record ∗

W.A. DiMichele,1 A.K. Behrensmeyer,1 T.D. Olszewski,2 C.C. Labandeira,1 J.M. Pandolfi,3 S.L. Wing,1 and R. Bobe1 1Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, DC 20560; email: [email protected], [email protected], [email protected], [email protected], [email protected] 2Department of Geology and Geo...

Investigation on the effects of some environmental factors on abundance and biodiversity of macrobenthos community in Karaj River

This article has no abstract.

Repetition & Stasis

Linking species abundance distributions in numerical abundance and biomass through simple assumptions about community structure.

Species abundance distributions (SADs) are widely used as a tool for summarizing ecological communities but may have different shapes, depending on the currency used to measure species importance. We develop a simple plotting method that links SADs in the alternative currencies of numerical abundance and biomass and is underpinned by testable predictions about how organisms occupy physical spac...