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Quaternary (2 mya) the effects of this forcing were going to get more pronounced and there started to
be the first glacials. By then a number of
Homo
species had evolved in Africa, including
Homo habilis
and
Homoerectus
,withacranialsizeroughlythree-quarters(orless)thatofmodernhumans.Oneoftheclosest
Homo
speciestoourselves(
H.sapiens sapiens
;or
H.sapiens
)was
Homosapiensneanderthalensis
(or
Homo
neanderthalensis
for short). It evolved from earlier
Homo
species but outside of Africa some 350000 years
ago.Thediminutive
Homoloresiensis
wassomewhatofanevolutionaryofshootodditythatprobablydied
out18000yearsago,wellbeforetheonsetofthecurrentinterglacial.Botharchaeologicalandgeneticana-
lysissuggeststhatmodernhumans,
H.sapiens
,evolvedin(possiblysub-Saharan)Africawithsomeremains
found in Ethiopia dating from 195000 years ago. Modern humans subsequently colonised the world. (For
detailsofhumangenomicanalysisseeLietal.,2008,andforamorecompletelistofearlydatesandsitesof
hominin remains see Carrion et al., 2011.) For a while
H.sapiens
shared southern Europe with
H.neander-
thalensis
beforethelatterwentextinctaroundthetimeoftheLGM.Thecurrentinterglacial(thebriefreturn
to cooler times in the Younger Dryas aside) began properly around 10000 years ago with
H. sapiens
then
beingtheonlyhumanspeciesontheplanet.
Datesregarding
H.sapiens
'Africanevolutionanddiasporaneedtobetreatedwithcautionduetolikely
problems,henceerror,indatingsuchieldsamples.Italsoshouldbenotedthatmuchevidenceisnotclear.
Stone tool remains, unless accompanied by fossil early human remains, cannot necessarily be attributed
to a specific hominin with certainty. Indeed, the phrase anatomically modern human (or AMH) lacks the
precision needed to elucidate a clear picture: anatomically modern humans can sometimes relate to more
thanonehomininspecies.Forexample,thereissomeindicationthatananatomicallymodernhuman(pos-
siblymodernhuman,possiblynot)populationmigratedoutofAfricabeforetheTobasuper-eruption74000
yearsago(Armitageetal.,2011).Thestudyofearlyhumanevolutionandmigrationhasseenanumberof
recent groundbreaking discoveries, which means that our understanding of what happened has changed
andprobablywillcontinuetodoso.
One evolutionary offshoot (quite probably from the
H. erectus
line) is that of
Homo floresiensis
(named after the island of Flores, east of Java, where the remains
of the first specimens were found in September 2003). Analysis (
14
C, luminescence,
uranium series and electron-spin resonance) suggests that
H. floresiensis
existed from
before 38 000 years ago (probably well before and perhaps as much as 800 000 years
ago) to as recently as 18 000 years ago (Morwood et al., 2004), although there has been
some speculation of continued survival to more recent times (now thought unlikely).
Either way, they therefore evolved either in the last glacial or over several glacials,
but whichever it is, it is likely that a glacial maximum, with its lower sea levels and
extensive land bridges, facilitated the island of Flores' initial habitation, even if some
sea crossing was required.
H. floresiensis
were short hominids of about 1 m in height with a chimpanzee-sized
brain (approximately 380 cm
3
), but which did use crude stone tools and fire. Whereas
climate change may very well have facilitated their getting to Flores, it was the limited
size of Flores itself, together with its semi-isolation, which facilitated the evolution
of
H. floresiensis
' short stature.
So, from Africa early human (
Homo
) species then migrated to other lands. Note:
modern humans (
H. sapiens
) evolved 195 000 years ago and then later left Africa,
possibly sometime between 85 000 and 55 000 years ago (most likely earlier in this
window than later) and probably entered Europe around or before 45 000 years ago.
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