Extinction event

An extinction event (also known as a mass extinction or biotic crisis) is a widespread and rapid decrease in the amount of life on Earth. Such an event is identified by a sharp change in the diversity and abundance of multicellular organisms. It occurs when the rate of extinction increases with respect to the rate of speciation. Because the majority of diversity and biomass on Earth is microbial, and thus difficult to measure, recorded extinction events affect the easily observed, biologically complex component of the biosphere rather than the total diversity and abundance of life.

Extinction occurs at an uneven rate. Based on the fossil record, the background rate of extinctions on Earth is about two to five taxonomic families of marine animals every million years. Marine fossils are mostly used to measure extinction rates because of their superior fossil record and stratigraphic range compared to land organisms.

The Great Oxygenation Event was probably the first major extinction event. Since the Cambrian explosion five further major mass extinctions have significantly exceeded the background extinction rate. The most recent and debatably best-known, the Cretaceous–Paleogene extinction event, which occurred approximately 66 million years ago (Ma), was a large-scale mass extinction of animal and plant species in a geologically short period of time. In addition to the five major mass extinctions, there are numerous minor ones as well and the ongoing mass-extinction caused by human activity is sometimes called the sixth extinction. Mass extinctions seem to be a mainly Phanerozoic phenomenon, with extinction rates low before large complex organisms arose.

Peter Ward

Peter Ward may refer to:

Peter Ward (rugby union)

Peter M. Ward (born 5 November 1876 – died 19??) was a rugby union player who represented Australia.

A fly-half, he was born in Invercargill, New Zealand and claimed a total of four international rugby caps for Australia. His Test debut was against Great Britain, at Sydney, on 24 June 1899, the inaugural rugby Test match played by an Australian national representative side.

Due to funding constraints he was one of only six New South Wales players (Charlie Ellis, Hyram Marks, Lonnie Spragg, Bob McCowan, and Robert Challoner were the others) selected to make the trip to Brisbane four weeks later for the second Test. His performance in that match was noted as excellent by the press.

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Peter Ward (footballer, born 1964)

Peter Ward (born 15 October 1964, Chester le Street, County Durham) is an English professional football manager who played over 350 Football League games as a midfielder. He was a player, manager, assistant manager and coach at Stockport County and is rumoured to be returning following the departure of Willie McStay. He also managed Morecambe as a caretaker between 1999-2000.

Playing career

Ward played for Chester le Street, Huddersfield Town, Rochdale, Stockport County, Wrexham and Morecambe. He started his career with the local Chester le Street town side and was spotted whilst playing in the Northern League by Huddersfield Town to whom he was subsequently transferred. Following a successful spell at the Yorkshire side where he featured alongside players such as Duncan Shearer he left for Spotland.

At Rochdale he helped the side into the 5th round of the FA Cup where they were defeated by Crystal Palace at Selhurst Park, in what was the clubs most successful ever run in the competition. On the way Rochdale defeated Whitley Bay from Ward's home region of the North East. His most successful spell in his professional career came when he moved onto Edgeley Park, playing under the legendary Uruguayan Manager, Danny Bergara, for Stockport County and this is where he met Jim Gannon. During his time at Stockport he played at Wembley four times, however he lost on each occasion. Ward was also renowned for his set pieces and his tough tackling. Ward then saw out his professional career with Welsh side Wrexham and later played briefly with Morecambe.