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Tuesday, December 15, 2009

Novel mtDNA M sublineage found in Madagascar


A new mtDNA M lineage has been detected among a Malagasy fisherman ethnicity: the
Vezo (4/101 = 4%). It's been named M16 and appears to hang directly from the M node. Three other individuals with this lineage have been found among African Americans (though it has not yet been detected in mainland Africa). M16 has also been found in one citizen of Dubai (UAE) and one (1/127 = 0.8%) among the Mikea hunter-gatherers/horticulturalists of SW Madagascar, believed to be a remnant of pre-Austronesian colonization of the island.

Haplogroup M16 is characterized by 11 coding region mutations and 8 control region ones. M16 has two subclades: M16a (found only in one Vezo individual) and M16b (including all other carriers). They estimate (following the new refined method of Soares et al. - but notice that they give a very recent age to the relevant Pan-Homo split: only 6.5 Mya, when it can well be of 8 and even 10 Mya for what I know) that the MRCA of this lineage lived some 9500 years ago (CI: 1.9-17 Kya), with that of M16b having lived 1700-3900 years ago (CI: 0-8.2 Kya).

Both Mikea and Vezo also show other ineages that are absent among the central Merina ethnicity (arguably a more direct descendant of Austronesian colonists), namely: M*, M7c3 and F3b.

Francois-X Ricaut et al., A new deep branch of eurasian mtDNA macrohaplogroup M reveals additional complexity regarding the settlement of Madagascar. BMC Genomics, 2009. Open access.


47 comments:

Kepler said...

Tatarabuelita M16 would be happy to know she left those descendants in such diverse places.

German Dziebel said...

There's another M16, also branching off from basal M16, that's found in Tibet. http://www.pnas.org/content/106/50/21230.abstract

Is there a connection between the two, I wonder, or geneticists are getting lost in the forest of their "deep rooting" lineages?

Maju said...

It's a matter of giving names: both papers are recent and M16 is the first blank in the M-number sequence. It happens somewhat often that novel clades discovered at about the same time are initially called with the same name, specially in M with its 40 or so sublineages (and more that are not directly hanging from the top but still keep their old M-number names).

Nomenclature in mtDNA is kinda crazy. But I don't have any reason to think they are the same or related in any manner (other than hanging from M).

terryt said...

"believed to be a remnant of pre-Austronesian colonization of the island".

I understand the evidence is pretty good that there was no-one there before the Austronesian colonization. Therefore Dubai M16 would be a remnant of the Austronesian passage to Madagascar, and fairly recent. So, if M16 brancehes off near the base of the M lineage we must conclude that M itself is relatively recent too.

terryt said...

Interesting link regarding Madagascar, and relevant to extinctions as well:

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WJS-4CYNN28-2&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1138625594&_rerunOrigin=google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=23112d849ac7732872467bc644a3fd28

Puts the settlement of Madagascar at around 300 BC, about the time the Austronesians were first able to reach as far west as Fiji, Tonga and Samoa.

Maju said...

Yes, there seems to be some evidence of pre-Austronesian presence in the island: the decline of megafauna and the mythology about the pale Pygmy-like people called Vazimba, now venerated as "ancestors", though also identified with some of the less Austronesian-like groups living in the great island.

I would agree though that M16 looks like could have been brought by Austronesians. The findings outside the island so far could perfectly be product of the slave or in general West Indian Ocean trade, in which Madagascar was not spared. The fact also that it's found almost exclusively among the Vezo fishermen also suggests an early Austronesian founding effect.

By mtDNA, the Vezo and Merina seem like 50-50 African and Asian, the Mikea instead look mostly African (84/127). It would have been interesting to research the L lineages, however these are dumped all together. Maybe another time...

terryt said...

I don't know that there is any evidence of a 'pre-Austronesian presence in the island'. We can't take seriously 'mythology about the pale Pygmy-like people called Vazimba, now venerated as ancestors'. Maori too have mythology of earlier pale people.

I suspect that such myths evolve because most families are descendants of immigrants, even if only from fairly adjacent regions. To justify replacing previous families the new people derive myths maintaining that the ealier people were very much different from, and especially inferior to, themselves. If a pre-Austronesian people had come from Africa they'd hardly be 'pale'. I'm almost certain that the African element in Madagascr postdates the SE Asian.

I made a mistake earlier. Around 300 BC is about the time the Austronesians were first able to [move beyond] Fiji, Tonga and Samoa. They'd arrived in those islands nearly a thousand years before.

Maju said...

I don't know that there is any evidence of a 'pre-Austronesian presence in the island'.

Hey! Your nothing less than your favorite one: extinction events, megafauna decline! That's what the paper says.

I just take their word on it. The fact that there are some groups that are hunter-gatherers speaks in favor of a previous colonization. I haven't checked the supplementary materials to check for the L(xM,N) specifics yet anyhow.

Maju said...

Never mind the supplemental material says nothing about the L(xM,N) lineages, just about matches of M16 around the world. Pity.

German Dziebel said...

"Therefore Dubai M16 would be a remnant of the Austronesian passage to Madagascar, and fairly recent. So, if M16 brancehes off near the base of the M lineage we must conclude that M itself is relatively recent too."

Yes. It must be younger than its sister clade, haplogroup D.

Maju said...

What's that quoted text from, Dziebel?

It makes no sense to me. The stem to M16 has 11 CR mutations, and a bunch of other HVS ones (more than 20 total). It's one of the longest mtDNA stems I know for any lineage.

M16 must be very recent but M is not: M16 just coalesced for a very long time in pre-M16 stages that we have no info about (but may still be around in Indonesia).

The Dubai presence can perfectly be for the same reason the lineage is found in the USA. Or do you think that Madagascar was spared in the slave trade?!

German Dziebel said...

The quote was from Terry. Use your search function, Aldamiz.

"M16 must be very recent but M is not: M16 just coalesced for a very long time in pre-M16 stages that we have no info about (but may still be around in Indonesia)."

Could those unattested stages be in fact attested in the phylogeny of D haplogroup? In India, D lineages look like relics from the time prior to the proliferation of M lineages.

Maju said...

My Coffee function, you mean?

Anyhow, you agreed with him...

terryt said...

"extinction events, megafauna decline! That's what the paper says".

Quite. And it says the extinctions took place about the same time as the Austronesians managed to move beyond Fiji, Tonga and Samoa. They had made it from Indonesia to as far as those islands a thousand years before then so they were obviously well placed to reach Madagascar by the time of the extinctions. So, no evidence for pre-Austronesians in Madagascar.

"The fact that there are some groups that are hunter-gatherers speaks in favor of a previous colonization".

Austronesians often became hunter-gatherers when they first reached many of the different islands. It was usually only with the depletion of original resources that they were forced to take up farming, often under the influence af later arrivals.

Maju said...

The background section reads:

Hippopotamus bones with cut-marks and evidence of human processing from iron tools have been found in the Mikea Forest, in Madagascar’s Southwest, dating to ~2 kyr [21]. Later archaeological sites, now containing pottery, have been variously dated from the 4th to the 8th centuries AD.

So all points out to the Mikea being older in Madagascar than Austronesian pottery carriers (even if they now also speak Austronesian).

This settlement pattern is further supported by dated faunal extinctions, as well as palaeoenvironmental evidence of deforestation indicated by a decrease in tree pollen and an increase in small charcoal pieces in soil sediments.

The latter should correspond to the Iron Age Austronesian arrival but the former does not necessarily and (from context) I understand it means that hippopotamuses and maybe other large prey went extinct soon after the African hunter-gatherer arrival, c. 2000 BCE (the text seems to mistakenly say "2 kyr" but context clearly indicates it's a typo or an implicit understanding of BCE dates).

terryt said...

"So all points out to the Mikea being older in Madagascar than Austronesian pottery carriers (even if they now also speak Austronesian)".

Not necessarily so at all. The authors seem unaware thet two thousand years is well within the period Austronesians were voyaging widely into the Pacific, so it's surely reasonable to suppose they were moving in the other direction as well. And just because they don't have pottery doesn't mean they weren't Austronesian speakers.

"The latter should correspond to the Iron Age Austronesian arrival"

The Austronesians were Iron Age? You are the only person who would refer to them as such.

"I understand it means that hippopotamuses and maybe other large prey went extinct soon after the African hunter-gatherer arrival, c. 2000 BCE (the text seems to mistakenly say '2 kyr' but context clearly indicates it's a typo or an implicit understanding of BCE dates)".

No. Not 'mistakenly say', deliberately say. The extinctions happened 2000 years ago, not 2000 BC.

terryt said...

Quote from the paper:

"Multiple lines of evidence point to the earliest human presence at ca. 2300 14C yr BP (350 cal yr BC). A decline in megafauna, inferred from a drastic decrease in spores of the coprophilous fungus Sporormiella spp. in sediments at 1720 ± 40 14C yr BP (230–410 cal yr AD), is followed by large increases in charcoal particles in sediment cores, beginning in the SW part of the island, and spreading to other coasts and the interior over the next millennium. The record of human occupation is initially sparse, but shows large human populations throughout the island by the beginning of the Second Millennium AD".

Maju said...

And just because they don't have pottery doesn't mean they weren't Austronesian speakers.

Does the fact that they were hunter-gatherers and not farmers, just like modern-day Mikea people, rings a bell?

Huntergatherers, without pottery nor steel... they are not just pre-Austronesian but also pre-Bantu and pre-Nilotic. That's why I was so interested in Mikea L lineages, because that could tell us a lot about pre-Bantu East Africa. For instance a high L2a would mean that this lineage was absorbed and not spread by Bantus, or L2b would mean direct relation with Pygmy and Hadza, while various lineages of L1, L3 and L4 (almost exclusive of East African click speakers) would also be highly informative.

The Austronesians were Iron Age? You are the only person who would refer to them as such.

Because I started reading about them from the viewpoint of Madagascar. I've always been fascinated by Africa, not so much by Asia.

Most of the expansion of Austronesians (after early colonization of some areas in Philippines and Indonesia) happened after 1200, which is almost totally within the Iron Age.

No. Not 'mistakenly say', deliberately say. The extinctions happened 2000 years ago, not 2000 BC.

Because you say so! They say that pottery from 700 BCE is more recent ("later"), hence can't be what you say. Re-read please.

Quote from the paper:

"Multiple lines of evidence point to the earliest human presence at ca. 2300 14C yr BP (350 cal yr BC). A decline in megafauna, inferred from a drastic decrease in spores of the coprophilous fungus Sporormiella spp. in sediments at 1720 ± 40 14C yr BP (230–410 cal yr AD), is followed by large increases in charcoal particles in sediment cores, beginning in the SW part of the island, and spreading to other coasts and the interior over the next millennium. The record of human occupation is initially sparse, but shows large human populations throughout the island by the beginning of the Second Millennium AD"
.

Fair enough: this means that the extinction happened essentially with the arrival of those pesky Austronesian farmers, who also caused extinctions elsewhere.

But the cutmarks in bones of hippopotamus are earlier than BCE pottery (which are "later"), hence must be older than just 2000 BP, it must be an error with 2000 BCE.

I'm positive that is the only interpretation possible.

terryt said...

You do have trouble understanding anything that doesn't fit with your preconceived ideas, don't you.

"The record of human occupation is initially sparse, but shows large human populations throughout the island by the beginning of the Second Millennium AD".

What is it that you don't understand about that comment? The previous sentence even states, 'beginning in the SW part of the island, and spreading to other coasts and the interior over the next millennium'. So, precisely in the region of your precious Mikea.

"Huntergatherers, without pottery nor steel... they are not just pre-Austronesian but also pre-Bantu and pre-Nilotic".

The NZ Maori had neither pottery nor steel. So, according to your reasoning they are not Austronesian. In fact they are probably 'pre-Bantu and pre-Nilotic'.

"Most of the expansion of Austronesians (after early colonization of some areas in Philippines and Indonesia) happened after 1200, which is almost totally within the Iron Age".

What? The Austronesian expansion from Taiwan began at least 5000 years ago, and probably nearer 7000. By 1200 BC they'd reached Fiji, Tonga and Samoa. And they certainly never had iron.

"They say that pottery from 700 BCE is more recent ('later'), hence can't be what you say. Re-read please".

I'll look for it soon. But I assume you're reading it wrong.

terryt said...

"But the cutmarks in bones of hippopotamus are earlier than BCE pottery (which are 'later'), hence must be older than just 2000 BP, it must be an error with 2000 BCE".

Can't find any reference to cutmarks on hippopotami. Where is it?

Anyway:

"Fair enough: this means that the extinction happened essentially with the arrival of those pesky Austronesian farmers, who also caused extinctions elsewhere".

But the article says:

"Multiple lines of evidence point to the earliest human presence at ca. 2300 14C yr BP (350 cal yr BC)".

Note, 'EARLIEST HUMAN PRESENCE'. Understand? So the extinctions' beginning coincides with these first arrivals. And these first arrivals were Austronesians. Africans arrived later. How else is it possible to interpret the statements?

Maju said...

Page 4 (or use the find feature, which is there for something):

The earliest archaeological evidence on the island is controversial. Hippopotamus bones with cut-marks and evidence of human processing from iron tools have been found in the Mikea Forest, in Madagascar’s Southwest, dating to ~2 kyr [21]. Later archaeological sites, now containing pottery, have been variously dated from the 4th to the 8th centuries AD. Therefore, the island seems to have been visited at least intermittently by Africans prior to the arrival of Austronesian-speaking maritime travellers from Island Southeast Asia sometime around the 7th or 8th centuries AD [18, 19, 22-25]. This settlement pattern is further supported by dated faunal extinctions, as well as palaeoenvironmental evidence of deforestation indicated by a decrease in tree pollen and an increase in small charcoal pieces in soil sediments [14, 24, 26].

Maju said...

From context, I conclude that "-2 kyr" means 2000 BCE. But it's confusing and hopefully will be changed for the definitive paper (this is provisional yet).

Maju said...

And these first arrivals were Austronesians. Africans arrived later. How else is it possible to interpret the statements?

The way I do.

The NZ Maori had neither pottery nor steel.

Not all Austronesians are Maori. And Malagassys are much more directly related to Malayo-Indonesians, seemingly to the ones from Borneo.

What? The Austronesian expansion from Taiwan began at least 5000 years ago...

That's not what Wikipedia says:

"According to mainstream Western studies, a large-scale Austronesian expansion began around 5000-2500 B.C. Population growth primarily fueled this migration. These first settlers may have landed in northern Luzon (...) Over the next thousand years, Austronesian peoples migrated southeast to the rest of the Philippine Islands, and into the islands of the Celebes Sea, Borneo, and Indonesia. The Austronesian peoples of Maritime Southeast Asia sailed eastward, and spread to the islands of Melanesia and Micronesia between 1200 B.C. and 500 A.D. respectively.

"(...) They had settled Easter Island by 300 A.D., Hawaii by 400 A.D., and into New Zealand by 800 A.D. In the Indian Ocean they sailed west from Maritime Southeast Asia; the Austronesian peoples reached Madagascar by 200 A.D.".

Most of the expansion happened, as you can read in CE (AD) times. Only the core expansion into Philippines and nearby islands is from earlier dates.

The colonization of Madagascar is dated in this article to 200 CE (while the paper dates it even later, at c. 700 CE).

terryt said...

"From context, I conclude that '-2 kyr' means 2000 BCE".

No it doesn't. It means what it says.

"Later archaeological sites, now containing pottery, have been variously dated from the 4th to the 8th centuries AD".

So pottery appears later, but I can't find any reference as to its being related to SE Asian pottery or to African. So the author's conclusion, 'Therefore, the island seems to have been visited at least intermittently by Africans prior to the arrival of Austronesian-speaking maritime travellers from Island Southeast Asia sometime around the 7th or 8th centuries AD' is completely unjustified. If they'd 'visited at least intermittently' surely they'd have stayed and multiplied. Such a productive environment would surely lead eventually to a population explosion, as has everywhere else. Madagascar would now be predominantly African. Besides which intermittent visiting implies a sophisticated boating technology. What happened to it?

"And Malagassys are much more directly related to Malayo-Indonesians, seemingly to the ones from Borneo".

But that doesn't mean at all they took pottery with them. Pottery obviously died out as the Austronesians crossed the Pacific too.

"That's not what Wikipedia says"

How many times have you criticised others for using Wiki as a reference? Anyway:

"The colonization of Madagascar is dated in this article to 200 CE"

That's reasonably close to 'Hippopotamus bones with cut-marks and evidence of human processing from iron tools have been found in the Mikea Forest, in Madagascar’s Southwest, dating to ~2 kyr'.

I'm not so sure about the iron tools, unless they picked them up along the route to Madagascar. From Wiki:

"a large-scale Austronesian expansion began around 5000-2500 B.C."

And:

"Over the next thousand years, Austronesian peoples migrated southeast to the rest of the Philippine Islands, and into the islands of the Celebes Sea, Borneo, and Indonesia".

That takes us to 1500 BC at the latest. The remainder of Wiki deals only with the eastward expansion. We can presume the westward one began about the same time, or shortly afterwards. After all, they could follow the coast for much of the journey west whereas they were usually sailing blind to the east.

I strongly suspect the reason that you are so committed to an early African presence on Madagascar is that you have trouble reconciling a crossing of the Bab Al Mandab in boats more than 50,000 years ago with an apparent lack of any further development of offshore boating in Africa for such a long time afterwards. I'm sorry. You'll have to live with it.

terryt said...

"The Austronesian peoples of Maritime Southeast Asia sailed eastward, and spread to the islands of Melanesia and Micronesia between 1200 B.C. and 500 A.D. respectively".

So their sailing technology was sufficient to reach the previously unoccupied islands of Melanesia by 1200 B.C. Easily sufficient to reach Madagascar, in the other direction, along the coast by 300 B.C.

terryt said...

Earlier I wrote, 'What? The Austronesian expansion from Taiwan began at least 5000 years ago...'

You replied, 'That's not what Wikipedia says'. But the first sentence in Wiki is:

"According to mainstream Western studies, a large-scale Austronesian expansion began around 5000-2500 B.C."

So what's the difference between what I wrote and what Wiki says? Your lack of reading skills shows up yet again.

Maju said...

Ok, you're right with the last thing. The expansion (from Taiwan to Philippines) could have begun as early as 5000 BCE maybe but also as late as 2500 BCE. Anyhow it's not too important because the jump to open ocean only happened much later in the last milennium BCE or the first milennium CE. It's virtually irrelevant when they crossed into Philippines for what we are discussing here.

No it doesn't. It means what it says.

Whatever. Remind me to check when the paper is corrected for publication. For me it's clear but if you don't want to admit it, it's your problem.

How many times have you criticised others for using Wiki as a reference? -

Not for doing it. Just criticized the reference when it was wrong. Wikipedia is not always right but it's a quick reference. If you think it's invalid in this particular case, present your counter-evidence please.

As for pottery I understand it clearly refers to the Austronesian arrival, as the dates are at least similar in all the texts I have ever read on the subject: Iron Age, CE dates. Anyhow this paper only makes an overview of the archaeological context and fails also to analyze the African DNA - it's just focused on their discovery of M16.

However it is interesting to know from it that some groups are believed to be pre-Austronesian colonists and that they were hunter-gatherers, hence also pre-Bantu (non-Bantu at least).

terryt said...

"For me it's clear but if you don't want to admit it, it's your problem".

For me it means exactly what it says, very clear. It's you who have the problem. I'm sure that 'when the paper is corrected for publication' it will read exactly the same.

"Anyhow it's not too important because the jump to open ocean only happened much later in the last milennium BCE or the first milennium CE".

And by the Austronesians were easily capable of reaching Madagascar.

"If you think it's invalid in this particular case, present your counter-evidence please".

I actually agree with it. It fits exactly with what I've said. By 1500 BC Austronesians were very adept sailors and by 2000 years ago they could easily reach Madagascar.

"However it is interesting to know from it that some groups are believed to be pre-Austronesian colonists and that they were hunter-gatherers, hence also pre-Bantu (non-Bantu at least)".

And the authors base that belief on mythology and the possibility that M16 branches off very early during OoA, and may even come from Africa. Although they do admit it's more likely to come from SE Asia.

"As for pottery I understand it clearly refers to the Austronesian arrival"

The only thing I've been able to find so far regarding Madagascar pottery from between the 4th to the 8th centuries AD is that it's not African. It could come from Arabia, India or Sri Lanka as much as from SE Asia.

Maju said...

What does -2000 (in years) might mean even out of context? 2000 BCE, obviously. I used to work with such negative numbers for long until I realized that most people did not style negative years and changed my style to adapt.

I have on the contrary never seen -2000 to mean "before present", sorry. It's always before Octavius or that fool they nailed to a plank in Plestine: BCE.

And by the Austronesians were easily capable of reaching Madagascar.

There's no way Austronesians could have reached Madagascar or any remote island as early as 2000 BCE. And it's not the kind of evidence we would expect either.

Plus being able is not the same as reaching it in fact. Austronesians never colonized the nearby islands of Mascaregnes or Seychelles. They never settled Maldivas or Japan or Australia... they reached to where they did in fact (a host of unpredictable random sum of individual and little groups' decisions) not where they were merely technically capable to reach.

Austronesians did not colonize most of the world. Even if they specialized in islands, they never settled any other island in the Indian Ocean.

Being able to is not the same as doig it. I'm able to go down for bread but I'm not doing it right now, maybe later, maybe I'll pass and call up the Chinese food delivery service again.

Although they do admit it's more likely to come from SE Asia.

Looks like but would need to be confirmed by finding at least related lineages in the Malay archipelago. In theory, Malay colonists could anyhow have picked the lineage anywhere in their route (South, West Asia, East Africa).

The only thing I've been able to find so far regarding Madagascar pottery from between the 4th to the 8th centuries AD is that it's not African. It could come from Arabia, India or Sri Lanka as much as from SE Asia.

Good enough: it's Malagassy farmer, what means Malay. Malagassy hunter-gatherer instead means Mikea.

terryt said...

"There's no way Austronesians could have reached Madagascar or any remote island as early as 2000 BCE".

And no-one, other than you, has even mentioned such a possibility. Certainly none of the papers we've discussed here claim it, and neither do I. And it should even be obvious, even to you, that the authors are not claiming such a date. Do you really believe people in Madagascar were cutting up hippopotami with iron tools 4000 years ago? Two thousand years ago is more likely. And that date has been accepted for about forty years now and is confirmed by the paper you presented. You can make things up if you like but you certainly won't convince me. Or, probably, anyone else here either.

"Even if they specialized in islands, they never settled any other island in the Indian Ocean".

They specialized in unoccupied islands. But of those, of course only the ones they happened to discover. They didn't have maps you know. The evidence is overwhelming that they were the first to discover Madagascar although, as you point out, they missed many small, isolated islands in the Indian Ocean. And they reached many isolated islands in the Pacific less than a thousand years ago.

"In theory, Malay colonists could anyhow have picked the lineage anywhere in their route (South, West Asia, East Africa)".

True, but there are plenty of M lines in SE Asia. In fact I remember recently a diagram that showed an M lineage (I forget which one, but I think perhaps related to an Andaman one) that seems to have expanded through the Indian state of Orissa from the coast.

"Malagassy hunter-gatherer instead means Mikea".

And the Mikea, too, were almost certainly originally Malays, although with later admixture with Africans. When people first arrive in any region with plenty of easlily available resources what incentive would they have to remain farmers? It's only once those resources become severely depleted that they are forced into farming.

Maju said...

And no-one, other than you, has even mentioned such a possibility.

I understand that the paper discussed here does: that hunter-gatherers appear to have colonized Madagascar from mainland SE Africa c. 2000 BCE (the Mikea would be their direct descendants, although somewhat mixed with Austronesian blood).

Do you really believe people in Madagascar were cutting up hippopotami with iron tools 4000 years ago? -

No. With stone tools. Where does it say "iron tools"? It says "cutmarks".

And they reached many isolated islands in the Pacific less than a thousand years ago.

Even if related, these were already two different peoples: Malays in Madagascar (and nowhere else) and Polynesians in Oceania (but not in the Indian Ocean). Two related but distinct processes.

True, but there are plenty of M lines in SE Asia.

I know but this one has not been detected. Nor elsewhere that matters, true.

And the Mikea, too, were almost certainly originally Malays...

No. They should not have reverted to hunter-gatherers, plus there is the datum of hippopotamus cutmarks in their area precisely.

It's only once those resources become severely depleted that they are forced into farming.

A fantasy generalization with no evidence. Proto-Malagassies arrived to Madagascar with rice and they have built their culture upon it. Would they done as you think, then they would have grown shorgum or whatever of the local African crops, not rice.

terryt said...

Maju:

"Where does it say 'iron tools'? It says 'cutmarks'".

The Paper:

"Hippopotamus bones with cut-marks and evidence of human processing from iron tools have been found in the Mikea Forest, in Madagascar’s Southwest, dating to ~2 kyr [21]".

Maju:

"I understand that the paper discussed here does: that hunter-gatherers appear to have colonized Madagascar from mainland SE Africa c. 2000 BCE"

The Paper:

"Multiple lines of evidence point to the earliest human presence at ca. 2300 14C yr BP (350 cal yr BC)".

Maju:

"Even if related, these were already two different peoples".

Me:

They were the same people until about 1500 BC. They spread originally from the islands in Wallacea, including the Philippines.

From Wikipedia:

"The Austronesian peoples of Maritime Southeast Asia sailed eastward, and spread to the islands of Melanesia and Micronesia between 1200 B.C. and 500 A.D. respectively. The Austronesian inhabitants that spread westward through Maritime Southeast Asia had reached some parts of mainland Southeast Asia, and later on Madagascar".

terryt said...

By the way:

"Proto-Malagassies arrived to Madagascar with rice and they have built their culture upon it".

Austronesian-speaking people certainly did not take rice into Melanesia. However what they did take was the agriculture the people in New Guinea and Northern Melanesia already possessed. In fact it is virtually certain the Austronesian-speaking people who moved further into the Pacific were a mixture. As probably were the people who first arrived in Madagascar according to this article, which I'm sure you'll find interesting:

http://ejournal.anu.edu.au/index.php/bippa/article/viewFile/662/641

Maju said...

Ok. You have persuaded me. The paper by Vérin and Wright is very conclusive and more to the substance than the one discussed in the post.

terryt said...

For what it's worth here is my summary of what we've learned.

I actually disagree with the statement in the article that the Melanesian Islands were the first uninhabited islands the Austronesians had reached. I strongly suspect that many islands in Wallacea and the South China Sea had become isolated and uninhabited with the rising sea level of 10Kya.

The key to the situation would be the Philippines. Do some surviving groups there predate the Austronesians? That's why I'm so interested in Spencer Wells' recent work there. He is yet to publish for some reason or other.

We can be sure that at least some of the islands south of Taiwan were unoccupied, with plenty of resources for the first human arrivals, or re-arrivals. We know that by 1500 BC Austronesian-speaking people had developed boating technology capable of bypassing the already occupied islands of New Guinea/Northern Melanesia and moving into the wide open seas beyond. To reach Fiji, Tonga and Samoa by 1000 BC; 3000 years ago. They were held up there for another thousand years though, over which period they became the proto-Polynesians.

To the west, on the other hand, Austronesians-speaking people had been able to enter uninhabited islands around Borneo and Java, from where they set off looking for more of them. The Andamans were already occupied so they bypassed them.

Once the Austronesians had reached Sri Lanka they were able to join the long-established trade routes in the Arabian Sea. In return they presumably did quite well transfering goods between Sri Lanka and Indonesia, even adopting some Buddhist words evidently. By the time of the early Roman Empire the Arabian Sea trading routes had extended well down the East African coast. But evidently not to Madagascar. The Austronesians were able to take advantage of that situation, and carry on their tradition of preferentially moving into unoccupied islands.

But extinctions were slow. Because they comprised a relatively small inbred group, they were unable to rapidly attain the island's human carrying capacity. This was not possible until some East Africans had adopted elements of the Austronesian boating technology and crossed to the island, mixing with the first arrivals. This has given rise to the paradoxical situation of African groups occupying coastal regions and the sea-going Austronesians the interior.

Maju said...

I think both Wallacea and near-New Guinea Melanesia were inhabited.

The key to the situation would be the Philippines. Do some surviving groups there predate the Austronesians?-

Of course: several Negrito groups.

I understand that all what is now the Malay Archipelago was inhabited when Austronesians arrived. Maybe a few small islands were not but that would be about it.

By the time that Austronesians are normally accepted to have reached Madagascar, there was already an array of their kingdoms in Indonesia. See: Srivijaya.

So they rather got involved in the Indian Ocean trade routes beginning from there.

But extinctions were slow. Because they comprised a relatively small inbred group...

Again with your "inbreeding" hypothesis for everything! They were not inbred: they have even now many different lineages.

This has given rise to the paradoxical situation of African groups occupying coastal regions and the sea-going Austronesians the interior.

Not exactly. The interior plateau was more suitable for agriculture, less strictly tropical. Austronesians were everywhere... just that in the interior they got less mixed with African natives. Anyhow Merina, the plateau realm, did not become really important until one or two centuries ago.

terryt said...

"Again with your 'inbreeding' hypothesis for everything!"

So what would be your explanation for how it's possible that recessive mutations can become established phenotypically within a population? Or do you maintain that such never happens? All genes present in all species today were present in God's original creation? Unfortunately the dual role of inbreeding and hybrid vigour in evolution is ignored by many, leading to a huge lack of understanding of the process.

"Of course: several Negrito groups".

You're a very brave man, Maju. Not many would claim so dogmatically that the Negritos in the Philippines are definitely pre-Austronesian. They speak Austronesian languages, although certainly there is a possibilty the language was adopted by a pre-existing population.

"The Negritos of the Philippines are comprised of approximately twenty-five widely scattered ethnolinguistic groups totaling an estimated 15,000 people. They are located on several major islands in the country: Luzon, Palawan, Panay, Negros, Cebu, and Mindanao".

(From this (not very good) link:

http://www.everyculture.com/East-Southeast-Asia/Philippine-Negritos.html

Note, major islands. The big ones. That still leaves many islands uninhabited when Austronesians first moved in, and leaves open the possibility that these Negritos were actually the first Austronesian-speaking people to enter Wallacea. Certainly the eastward-moving Austronesians were not as East Asian-looking as are present day Filipinos.

Here's a link that deals with pre-Austronesian Wallacea. Its focus is actually on the Andamans but it's very useful:

http://www.andaman.org/BOOK/chapter25/text25.htm

Maju said...

So what would be your explanation for how it's possible that recessive mutations can become established phenotypically within a population?-

Founder effect.

You're a very brave man, Maju. Not many would claim so dogmatically that the Negritos in the Philippines are definitely pre-Austronesian. They speak Austronesian languages, although certainly there is a possibilty the language was adopted by a pre-existing population.

I understand that not just many but EVERYBODY claims that. Maybe you are the exception.

Or how do you explain the striking phenotype differences between Negritos and regular Austronesians? Sure, Australian Aboriginals now speak English... but they don't come from England.

... leaves open the possibility that these Negritos were actually the first Austronesian-speaking people to enter Wallacea.

This suggestion lacks absolutely any merit, I am not going to waste any energies discussing it.

Certainly the eastward-moving Austronesians were not as East Asian-looking as are present day Filipinos.

It has been demonstrated that they are mixed with Melanesians (and Negritos maybe? - Philippines' Negritos are maybe the only major Eurasian branch still ill-researched genetically) and have founder effects (or "inbreeding", as you like to call it) of their own. Just what any normal person would expect. What else?

Maju said...

Anyhow, the last link you provided, Terry, is rather informative, thanks (had not read on Toalean before nor was aware of sites dated to c. 40 Kya in Timor either). But I don't see how can you argue against Negritoid populations being widespread in nearly all islands with such archaeological continuity and so much "island hopping" being involved.

This doesn't mean that Austronesian farmers and advanced seafarers would not be able to displace them (or absorb them) with relative ease when they arrived.

Whatever the case, I see no point on your insistence on such "desert islands". It doesn't really matter, does it?

terryt said...

"Founder effect".

But that would still only work if it resulted in inbreeding. So we're back with inbreeding. Recessive genes can only be expressed if an individual has a double dose. Assuming the particular mutation has only happened once (a reasonable assumption I'm sure you'll agree) it can only be expressed once two individuals of common descent mate. Of course this may happen long after the mutation occurred. And we know from intensive study of dairy cattle that most mutations that actually give rise to genes give rise to recessive ones. This is just as well or most of us wouldn't survive. Any disadvantageous dominant mutation would prevent survival.

"Or how do you explain the striking phenotype differences between Negritos and regular Austronesians?"

So what do you think 'regular Austronesians' look like? Austronesian-speaking people have always been very mixed, right from their origin. As I've pointed out elsewhere the east Asian phenotype is invasive to the region south of Taiwan, and probably so for regions considerably to the north of that island.

"Philippines' Negritos are maybe the only major Eurasian branch still ill-researched genetically)"

Spencer Wells collected DNA samples from them more than a year ago but is yet to publish anything. I assume he did the research for National Geographic but I suspect something he found didn't turn out the way he expected.

"It doesn't really matter, does it?"

Deserted islands would certainly explain their rapid expansion south from Taiwan, and is certainly so for their expansion beyond the Northern Solomons.

Maju said...

But that would still only work if it resulted in inbreeding.

Whatever. I don't make much of an issue with this inbreeding matter. Most if not all species are the result of some degree of "inbreeding", it just depends what you want to emphasize.

I use terms such as founder effect and homogenization, which is similar to your "inbreeding" concept but does not hold negative eugenic connotations that may well be misleading and aprioristic. Some "inbreeding" is just normal in any population: people have always married within the tribe, the caste, the class, the village, the valley... at least much more often than outside these circles. So yes, population tend to become somewhat homogeneous because of that.

But I think your use and abuse of terms like "inbreeding" is unjustified. Inbred in the sense you mean was Charles II of Spain, but look at his family tree!

Reading on the concept of inbreeding, I have found this article that claims that some genetic affinity (3rd or 4th degree cousins) is favorable, rather than negative.

Instead there's also a concept called outbreeding depression, that implies that too unrelated couples are not necessarily good. This probably affected all Sapiens-Neanderthal offspring that existed.

But as you are the expert of inbreeding and outbreeding, you should be the one teaching me about these issues, not the opposite.

Maju said...

"So what do you think 'regular Austronesians' look like?"

Like this guy, for instance (a Taiwanese aborigine). Or like these guys, who look so typically Polynesian (but are Taiwanese). Or like this woman (again a Taiwanese).

"As I've pointed out elsewhere the east Asian phenotype is invasive to the region south of Taiwan, and probably so for regions considerably to the north of that island".

I may admit the first part rather reluctantly but I cannot admit the latter. It's mostly speculation.

Genetics don't seem to support that.

"Spencer Wells collected DNA samples from them more than a year ago but is yet to publish anything. I assume he did the research for National Geographic but I suspect something he found didn't turn out the way he expected".

So your reference for all that is Austronesian and Wallacean is a cheater? Hmmm...

"Deserted islands would certainly explain their rapid expansion south from Taiwan, and is certainly so for their expansion beyond the Northern Solomons".

First, the expansion south of Taiwan was not initially "rapid". Second, islands populated only by low density hunter-gatherers would be virtually the same thing.

terryt said...

Can't find your first link but the other two could just as easily be indigenous North Americans. Like I say, Austronesians are a mix of various groups and not paricularly distinctive.

terryt said...

"But I think your use and abuse of terms like 'inbreeding' is unjustified".

No. I use the term to mean your 'terms such as founder effect and homogenization', both of which are inadequate to explain the process. Founder effect is not necessarily inbreeding, unless the founder population is already inbred. Homogenization is closer but doesn't imply any limitation in population size, so is less effective in establishing new recessive genetic combinations.

"Inbred in the sense you mean was Charles II of Spain"

No. That's extreme. Offspring survival is compromised in such situations so it's too extreme for establishing recessive gene combinations.

I remember the paper about 3rd and 4th cousins. It indicates that outbreeding depression may begin at that level. In fact I remember making a comment to that effect in the blog concerned.

Maju said...

No. That's extreme.

That's true inbreeding and not whatever you're talking about that rather would be close to the seemingly optimal of 3rd-4th degree cousins.

I remember the paper about 3rd and 4th cousins. It indicates that outbreeding depression may begin at that level.

Actually indicates that the concept of inbreeding can only be applied to quite closer relationships and/or the systematic repetition of such close-relation breeding, as in the case of poor King Charles. This is not likely to happen in any human population, even if small.

So quit babbling "inbreeding" once and again!

According to Dr. Bruce Buehler, director of HBM Genetics at the University of Nebraska Medical Center, the chances of married siblings passing down an unfavorable recessive gene is one in 16, while, for first cousins, the chances are one in 64.

"At least genetically, this information doesn't suggest that second or third cousins would be at any higher risk for passing down unfavorable traits," Buehler said
.

However no positive explanation has been offered for that improved productivity either. As Buehler suggests, it may be more at the psycho-emotional level where this extra productivity is generated. This might be in fact checked in the lab by controlled insemination of, say, mice but suppressing the emotional bond aspect (if such thing exists in mice couples, what I doubt).

But it says absolutely nothing about the outbreeding depression starting there. Nothing at all suggests that.

terryt said...

"However no positive explanation has been offered for that improved productivity either".

Most practical geneticists would say it's because disadvantageous recessive genes have more chance of being offset by dominant ones.

"But it says absolutely nothing about the outbreeding depression starting there".

If individuals closer than 3 or4 generations are less productive of offspring and those more than 3 or 4 generations apart are less productive surely maximum heterosis is achieved at 3 or 4 generations. Anything closer is inbreeding depression and anything further is outbreeding depression. Of course it's impossible to define exactly where the line should be drawn because it depends on exactly which genes combine in each particular case. And the fading off of inbreeding or outbreeding depression is extremely gradual.

Maju said...

Just a baseless speculation, IMO.

Of course it's impossible to define exactly where the line should be drawn...

Why? All that can be tested in fruit flies, mice, arabidopsis, etc. Mice specially are a very good reference for humans.

It is possible.