Month: September 2022

RAPID RESTART. “We emphasise the astonishing speed of biological diversification following a ‘catastrophic’ mass extinction. We could refer to this feature as ‘catastrophic biological diversification’.” https://lnkd.in/eRbPBJq View in LinkedIn

FULL RECOVERY. “It appears likely that for mass extinction episodes in the geological past, the recovery period usually lasted at least five million years.” https://lnkd.in/eyRBipn View in LinkedIn

CAMBRIAN PUZZLE. “Abrupt appearance of major bilaterian clades in the fossil record during the first three stages of the Cambrian Period has puzzled the scientific world since 1830s.” https://lnkd.in/ehHwFGP View in LinkedIn

“THE ENIGMA that is the Cambrian Explosion is one of the most perplexing, fascinating, and important events in the evolution of life on Earth. Enigmatic due to the lack of evidence, and that which we do have is not necessarily clear in its implications producing an array of varying views, and hypotheses.” https://lnkd.in/ex6BW5w View in LinkedIn

BODY PLAN DIVERSITY. “The Cambrian explosion is named for the geologically sudden appearance of numerous metazoan body plans (many of living phyla) between about 530 and 520 million years ago, only 1.7% of the duration of the fossil record of animals.” https://lnkd.in/eagvRCB View in LinkedIn

SINGLE POINT EXPLOSION. “We owe the great diversity that we see today (plus or minus 10 million species) to the incredible diversification that occurred during the Cambrian period.” https://lnkd.in/ex6BW5w View in LinkedIn

SINGLE CAMBRIAN ORIGIN. “Evidence of metazoan activity in both trace and body fossils then increased during the 13 million years leading to the explosion. All living phyla may have originated by the end of the explosion.” http://dev.biologists.org/content/develop/126/5/851.full.pdf View in LinkedIn

“NO NEW PHYLA have evolved since the Cambrian.” Meditate on this one. https://lnkd.in/ex6BW5w View in LinkedIn

LATER COMPLEXIFICATION. “There was a major diversification known as the Ordovician Radiation, in the period immediately following the Cambrian. This event is unique in taxonomic, ecologic and biogeographic aspects. While all of the phyla but one were established during the Cambrian explosion, taxonomic increases during the Ordovician were manifest at lower taxonomic levels although ordinal level diversity doubled.” https://lnkd.in/eVq28Qh View in LinkedIn

DIVERSIFICATION CONTINUED. “Marine family diversity tripled and within clade diversity increases occurred at the genus and species levels. The Ordovician radiation established the Paleozoic Evolutionary Fauna; those taxa which dominated the marine realm for the next 250 million years. Community structure dramatically increased in complexity.” https://lnkd.in/eVq28Qh View in LinkedIn