Selectivity patterns provide insights into the causes of ancient extinction events. The Late Ordovician mass extinction was related to Gondwanan glaciation; however, it is still unclear whether elevated extinction rates were attributable to record failure, habitat loss, or climatic cooling.

Modern climate change has a strong potential to shift earth systems and biological communities into novel states that have no present-day analog, leaving ecologists with no observational basis to predict the likely biotic effects.

According to the ‘Faint Young Sun’ paradox, during the late Archaean eon a Sun approximately 20% dimmer warmed the early Earth such that it had liquid water and a clement climate. Explanations for this phenomenon have invoked a denser atmosphere that provided warmth by nitrogen pressure broadening or enhanced greenhouse gas concentrations. Such solutions are allowed by geochemical studies and numerical investigations that place approximate concentration limits on Archaean atmospheric gases, including methane, carbon dioxide and oxygen.

Acheulean/Acheulian denotes an archaeological industry of stone tool manufacture associated with early humans during the lower Palaeolithic era across Africa and much of West Asia, South Asia and Europe. The Palaeolithic era is a prehistoric era distinguished by the development of the most primitive stone tools discovered and covers roughly 99% of human technological prehistory. It extends from the earliest known use of stone tools, probably by hominins such as Australopithecines, 2.6 million years ago, to the end of the Pleistocene around 10,000 BP.

Some claim climate change will destroy our species; now it seems it also helped forge it. The rapid fluctuations in temperature that characterised the global climate between 2 and 3 million years ago coincided with a golden age in human evolution.

Palaeontologists characterize mass extinctions as times when the Earth loses more than three-quarters of its species in a geologically short interval, as has happened only five times in the past 540 million years or so. Biologists now suggest that a sixth mass extinction may be under way, given the known species losses over the past few centuries and millennia.

Salt Lake City: Scientists said that they

Mumbai: It came before the dinosaurs. It existed on this planet 350 million years ago, and survived for almost 80 million years before it became extinct. On Saturday, it will be back from the dead

Chief Minster Shivraj Singh Chouhan chaired a meeting of State Wildlife Board here today which recommended setting up of National Dinosaur Fossil Park near Bagh in Dhar district. More than 100 dinosaur eggs were found in Bagh in Dhar district in the year 2006, which are estimated to be 6.5 crore to 7 crore years old. Besides, fossilised dinosaur nests have also been found in the district.

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