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Showing posts with the label extinct

Warm pockets during cold times and a rediscovered species

For the last 6 million years or so, the Earth has been subjected to drastic temperature fluctuations. During the Pliocene, the Earth underwent cycles of warm wet and cooler dry periods. Substantial continental ice began to form in the Northern Hemisphere around 3 million years ago (Mya), before the planet was plunged into a series of ice ages. Although you may think of an "ice age" as a snowy period after which woolly mammoths and neanderthals disappeared, you may not know that currently we are simply enjoying a "summer" break from this ice age. The last 2 millions years of Earth's history has consisted of various glacial periods interspersed by warmer times, known as interglacial periods.

Madagascar's Lucky Break and Endemic Invaders

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Evolutionary consequences of Madagascar's isolation on extinct and extant vertebrate fauna © O'Reilly, X. (2010) Madagascar lies off the heal of the African continent. The world’s fourth largest island, on the map it is dwarfed by Africa’s shadow – but only in size.  Famous for the immense variety of weird and wonderful organisms it is home to, most of which are found nowhere else, Madagascar’s unique biological catalogue is the result of millions of years of evolution in isolation, as well as its dramatically varied relief. Its most famous inhabitants, by far, are the lemurs – a whole group of endemic primates that come in a variety of forms, each uniquely adapted to specific niches throughout island’s amazing range of habitats.   But lemurs are thought to have arrived on the island after its split from Africa – what was living on Madagascar at the time of its birth? What proportion of its current terrestrial vertebrate fauna actually split away with the is...