Early human speciation, brain expansion and dispersal influenced by African climate pulses.
Early human evolution is characterised by pulsed speciation and dispersal events that cannot be explained fully by global or continental paleoclimate records. We propose that the collated record of ephemeral East African Rift System (EARS) lakes could be a proxy for the regional paleoclimate conditi...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2013-01-01
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| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC3797764?pdf=render |
| _version_ | 1830460502551035904 |
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| author | Susanne Shultz Mark Maslin |
| author_facet | Susanne Shultz Mark Maslin |
| author_sort | Susanne Shultz |
| collection | DOAJ |
| description | Early human evolution is characterised by pulsed speciation and dispersal events that cannot be explained fully by global or continental paleoclimate records. We propose that the collated record of ephemeral East African Rift System (EARS) lakes could be a proxy for the regional paleoclimate conditions experienced by early hominins. Here we show that the presence of these lakes is associated with low levels of dust deposition in both West African and Mediterranean records, but is not associated with long-term global cooling and aridification of East Africa. Hominin expansion and diversification seem to be associated with climate pulses characterized by the precession-forced appearance and disappearance of deep EARS lakes. The most profound period for hominin evolution occurs at about 1.9 Ma; with the highest recorded diversity of hominin species, the appearance of Homo (sensu stricto) and major dispersal events out of East Africa into Eurasia. During this period, ephemeral deep-freshwater lakes appeared along the whole length of the EARS, fundamentally changing the local environment. The relationship between the local environment and hominin brain expansion is less clear. The major step-wise expansion in brain size around 1.9 Ma when Homo appeared was coeval with the occurrence of ephemeral deep lakes. Subsequent incremental increases in brain size are associated with dry periods with few if any lakes. Plio-Pleistocene East African climate pulses as evinced by the paleo-lake records seem, therefore, fundamental to hominin speciation, encephalisation and migration. |
| first_indexed | 2024-12-21T11:13:11Z |
| format | Article |
| id | doaj.art-a8d9094a8d0040789fa3e4dd1aa1e944 |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-21T11:13:11Z |
| publishDate | 2013-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-a8d9094a8d0040789fa3e4dd1aa1e9442022-12-21T19:06:01ZengPublic Library of Science (PLoS)PLoS ONE1932-62032013-01-01810e7675010.1371/journal.pone.0076750Early human speciation, brain expansion and dispersal influenced by African climate pulses.Susanne ShultzMark MaslinEarly human evolution is characterised by pulsed speciation and dispersal events that cannot be explained fully by global or continental paleoclimate records. We propose that the collated record of ephemeral East African Rift System (EARS) lakes could be a proxy for the regional paleoclimate conditions experienced by early hominins. Here we show that the presence of these lakes is associated with low levels of dust deposition in both West African and Mediterranean records, but is not associated with long-term global cooling and aridification of East Africa. Hominin expansion and diversification seem to be associated with climate pulses characterized by the precession-forced appearance and disappearance of deep EARS lakes. The most profound period for hominin evolution occurs at about 1.9 Ma; with the highest recorded diversity of hominin species, the appearance of Homo (sensu stricto) and major dispersal events out of East Africa into Eurasia. During this period, ephemeral deep-freshwater lakes appeared along the whole length of the EARS, fundamentally changing the local environment. The relationship between the local environment and hominin brain expansion is less clear. The major step-wise expansion in brain size around 1.9 Ma when Homo appeared was coeval with the occurrence of ephemeral deep lakes. Subsequent incremental increases in brain size are associated with dry periods with few if any lakes. Plio-Pleistocene East African climate pulses as evinced by the paleo-lake records seem, therefore, fundamental to hominin speciation, encephalisation and migration.http://europepmc.org/articles/PMC3797764?pdf=render |
| spellingShingle | Susanne Shultz Mark Maslin Early human speciation, brain expansion and dispersal influenced by African climate pulses. PLoS ONE |
| title | Early human speciation, brain expansion and dispersal influenced by African climate pulses. |
| title_full | Early human speciation, brain expansion and dispersal influenced by African climate pulses. |
| title_fullStr | Early human speciation, brain expansion and dispersal influenced by African climate pulses. |
| title_full_unstemmed | Early human speciation, brain expansion and dispersal influenced by African climate pulses. |
| title_short | Early human speciation, brain expansion and dispersal influenced by African climate pulses. |
| title_sort | early human speciation brain expansion and dispersal influenced by african climate pulses |
| url | http://europepmc.org/articles/PMC3797764?pdf=render |
| work_keys_str_mv | AT susanneshultz earlyhumanspeciationbrainexpansionanddispersalinfluencedbyafricanclimatepulses AT markmaslin earlyhumanspeciationbrainexpansionanddispersalinfluencedbyafricanclimatepulses |