THE HUXLEY MEMORIAL LECTURE

will be given by

Professor Chris Stringer, Natural History Museum

Tuesday 7 November 2023 at 1.30 pm in the Flett Lecture Theatre, Natural History Museum, South Kensington, London SW7 5BD and on Zoom.

Mostly Out of Africa: how, when and where

During the last 50 years the Recent African Origin model has risen from nowhere to become the dominant explanation for the origins of our species Homo sapiens. However, there are many outstanding issues in resolving the details of how, when and where we evolved. It is not yet clear whether the last common ancestor (LCA) of H. sapiens, Neanderthals, and Denisovans lived in Europe, Asia, or Africa, and when it lived. Estimates using genomic data from H. sapiens, Neanderthals, and Denisovans calibrate the LCA to between about 500,000 and 700,000 years ago. However, some recent stud­ies of dental and cranial variation in fossil hominins place the LCA earlier, between about 800,000 and 1.2  million years ago. Thus identifying potential candidate fossils for the LCA is highly problematic against these uncertainties. Moreover, some genetic models for the deep ancestry of H. sapiens and Neanderthals suggest that concepts of a single LCA in time and space might be illusory.

A further problem is that the fossil human record from Africa for the period between about 200,000 and 1 million years ago is relatively sparse, and yet this timespan was the critical one for the evolution of Homo sapiens. The record we have is generally not well-dated, and limited to small areas of the continent, with no fossils at all from large regions of West and Central Africa. In the past, researchers have proposed a range of different models, from those with a single location of origin (usually East or South Africa, which have the best fossil records for the period) through to pan-African models (sometimes also called African multiregionalism, a term I prefer not to use now because of potential confusion with the refuted global multiregional theory). Pan-African models envisage lineages of basal H. sapiens populations in different regions of Africa that evolved separately at times, but which also sporadically mixed and merged with each other, finally giving rise to the form of Homo sapiens that eventually spread globally.

That global spread is usually assumed to have been initiated about 60,000 years ago, but there is increasing evidence of earlier dispersals from Africa, at least one of which led to an episode of gene flow with a basal Neanderthal lineage. We now know that the main dispersal was also accompanied by bouts of gene flow with the Neanderthal and Denisovan lineages – hence the term Mostly Out of Africa (which I first heard being used by Svante Pääbo) is the most appropriate simple description for the evolutionary origins of our species.

Booking

Places for the Huxley Lecture and RAI AGM must be booked in advance.

To book an in person ticket for the Huxley Lecture and RAI AGM please go to https://www.eventbrite.co.uk/e/huxley-lecture-and-rai-agm-tickets-726815714367?aff=oddtdtcreator

To register to take part on Zoom please go to https://us02web.zoom.us/meeting/register/tZcvc--rqjksGdXKj0dO4S1wrVMPVmdDxMRC

If you are interested in the Mostly Out of Africa conference on 6 & 7 November that proceeds these events tickets can be purchased here https://www.eventbrite.co.uk/e/mostly-out-of-africa-conference-and-huxley-lecture-tickets-726781863117?aff=oddtdtcreator (if you book a ticket for the conference this automatically includes a ticket for the Huxley Lecture and RAI AGM, you do not need to book separately for this).

Location: Flett Lecture Theatre
Natural History Museum
South Kensington
London
SW7 5BD