john hawks weblog

paleoanthropology, genetics and evolution

glaciations

  • Reindeer associations

    Sat, 2012-12-22 22:50 -- John Hawks

    Alice Roberts ponders the prehistory of people and reindeer: "Rudolph and our early ancestors – a love story".

    The end of the ice age saw a massive global extinction: many large mammals fell prey to changing climate and the effect of some rather formidable hunters sharing their landscape. There was a decline in the genetic diversity of reindeer after the peak of the last ice age 20,000 years ago – probably due to a warming climate as well as those palaeolithic hunters – but reindeer survived, and thankfully they don't look likely to become extinct any time soon.

    Tags: 
    fauna
    glaciations

  • Late advance of the Swedish ice

    Sat, 2009-01-10 22:09 -- John Hawks

    News on an interesting dissertation about the last glaciation:

    According to the previously accepted hypothesis, Sweden was covered with ice 75,000-20,000 years ago. Martina Hättestrand’s hypothesis, on the other hand, is that Sweden may have largely been ice-free between 59,000 and 40,000 years ago. If this is true, the last ice sheet of the Ice Age formed much more rapidly than was previously believed in order to have reached all the way down to northern Germany during the maximum phase about 22,000 years ago.

    Tags: 
    climate
    Late Pleistocene
    paleoclimate
    glaciations

  • End of the ice age, cored

    Sun, 2008-12-28 09:25 -- John Hawks

    A Danish newspaper reports on some recent ice core research:

    A Danish ice drilling project has conclusively ended the discussion on the exact date of the end of the last ice age.

    The extensive scientific study shows that it was precisely 11,711 years ago - and not the indeterminate figure of ‘some’ 11,000 years ago – that the ice withdrew, allowing humans and animals free reign.

    ...

    “Our new, extremely detailed data from the examination of the ice cores shows that in the transition from the ice age to our current warm, interglacial period the climate shift is so sudden that it is as if a button was pressed”, explains ice core researcher Jørgen Peder Steffensen, Centre for Ice and Climate at NBI at the University of Copenhagen.

    These rapid climate reversals seem to have been a growing theme for the last decade or so. I think a review of chronology of the last 40,000 years might be in order here. I'll put it on my list.

    Tags: 
    glaciations
    paleoclimate
    Holocene
    Pleistocene
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Neandertals

For years, I've worked on their bones. Now I'm working on their genes. Read more about the science studying these ancient people.

Denisova

From a finger bone of an ancient human came the record of a completely unexpected population. My lab is working on the science of the Denisova genome.

Acceleration

The advent of agriculture caused natural selection to speed up greatly in humans. We're uncovering some of the ways that populations have rapidly changed during the last 10,000 years.

Malapa

Just outside Johannesburg, the Malapa site is producing some of the most exciting finds in human evolution. This site is the headquarters of the Malapa Soft Tissue Project.