Legacy of human migration on the diversity of languages in the Americas

12 09 2018

quechua-foto-ale-glogsterThis might seem a little left-of-centre for CB.com subject matter, but hang in there, this does have some pretty important conservation implications.

In our quest to be as transdisciplinary as possible, I’ve team up with a few people outside my discipline to put together a PhD modelling project that could really help us understand how human colonisation shaped not only ancient ecosystems, but also our own ancient cultures.

Thanks largely to the efforts of Dr Frédérik Saltré here in the Global Ecology Laboratory, at Flinders University, and in collaboration with Dr Bastien Llamas (Australian Centre for Ancient DNA), Joshua Birchall (Museu Paraense Emílio Goeldi, Brazil), and Lars Fehren-Schmitz (University of California at Santa Cruz, USA), I think the student could break down a few disciplinary boundaries here and provide real insights into the causes and consequences of human expansion into novel environments.

Interested? See below for more details?

Languages are ‘documents of history’ and historical linguists have developed comparative methods to infer patterns of human prehistory and cultural evolution. The Americas present a more substantive diversity of indigenous language stock than any other continent; however, whether such a diversity arose from initial human migration pathways across the continent is still unknown, because the primary proxy used (i.e., archaeological evidence) to study modern human migration is both too incomplete and biased to inform any regional inference of colonisation trajectories. Read the rest of this entry »

Cleaning up the rubbish: Australian megafauna extinctions

15 11 2013

diprotodonA few weeks ago I wrote a post about how to run the perfect scientific workshop, which most of you thought was a good set of tips (bizarrely, one person was quite upset with the message; I saved him the embarrassment of looking stupid online and refrained from publishing his comment).

As I mentioned at the end of post, the stimulus for the topic was a particularly wonderful workshop 12 of us attended at beautiful Linnaeus Estate on the northern coast of New South Wales (see Point 5 in the ‘workshop tips’ post).

But why did a group of ecological modellers (me, Barry Brook, Salvador Herrando-Pérez, Fréd Saltré, Chris Johnson, Nick Beeton), ancient DNA specialists (Alan Cooper), palaeontologists (Gav Prideaux), fossil dating specialists (Dizzy Gillespie, Bert Roberts, Zenobia Jacobs) and palaeo-climatologists (Michael Bird, Chris Turney [in absentia]) get together in the first place? Hint: it wasn’t just the for the beautiful beach and good wine.

I hate to say it – mainly because it deserves as little attention as possible – but the main reason is that we needed to clean up a bit of rubbish. The rubbish in question being the latest bit of excrescence growing on that accumulating heap produced by a certain team of palaeontologists promulgating their ‘it’s all about the climate or nothing’ broken record.

Read the rest of this entry »

Declining biodiversity in… your filthy mouth

18 02 2013

green teethIt still amazes me that the more we look, the more we realise just how important intact ecosystems are for our own well-being. I guess this is why I’m still a scientist.

Our latest paper that just came out today in Nature Genetics is a bit of a departure for me (again!); I really must not take much credit for this given that it was a huge effort among a big team of people and I played a comparatively minor role. Still, I can definitely say this is one of the more interesting papers I’ve co-authored in a while.

For me the involvement started after Alan Cooper (Director of the Australian Centre for Ancient DNA) asked me for a bit of help with a cool paper he and some of his colleagues were working on. When he told me what the subject was, my initial reaction was (yawn): Dentistry? Teeth? You’ve got to be joking. Why would an ecologist be even remotely interested in that stuff? Then he went into more detail, and I was hooked.

Before I get into that detail, I have to tell you a story about a colleague of mine (name withheld, but true story) who recently went to the dentist to have some routine cleaning and maintenance done. There was nothing particularly special about his visit – no local anaesthetic, no extractions, no caps, and certainly no surgery. Two weeks later he was in the hospital theatre getting his chest cracked open for open-heart surgery. Jesus H. Christ!, I said to myself. Read the rest of this entry »

Hades, fossilised fat-parrot shit and threatened bats

4 10 2012

WTF? © P. Bendle

Sounds like a Monty Python sketch, doesn’t it? But no, it’s about the wonderful complexity of ecology.

An interesting, and very weird paper just came out in Conservation Biology co-authored by my friend and colleague, Prof. Alan Cooper at the Australian Centre for Ancient DNA (ACAD).

Here’s what they have to say about it.

Ancient dung from a cave in the South Island of New Zealand has revealed a previously unsuspected relationship between two of the country’s most unusual threatened species.

Fossilised dung (coprolites) of a now rare parrot, the nocturnal flightless kakapo, contained large amounts of pollen of a rare parasitic plant, Dactylanthus, which lives underground and has no roots or leaves itself. The pollen suggests the kakapo was formerly an important pollinator for the threatened species, known as the Hades flower or wood rose. Researchers from the Australian Centre for Ancient DNA at The University of Adelaide, and Landcare Research and the Department of Conservation in New Zealand report the discovery in the journal Conservation Biology.

Read the rest of this entry »

Ghosts of bottlenecks past

25 05 2012

© D. Bathory

I’ve just spent the last week at beautiful Linnaeus Estate on the northern NSW coast for my third Australian Centre for Ecological Analysis and Synthesis (ACEAS) (see previous post about my last ACEAS workshop).

This workshop is a little different to my last one, and I’m merely a participant (not the organiser) this time. Alan Cooper and members of his Australian Centre for Ancient DNA (Jeremy Austin, Vicki Thomson & Julien Soubrier) combined forces this week with Craig Mortiz, Margaret Byrne, Steve Donnellan, Tania Laity, Leo Joseph, Xander Xue and Gabriele Cybis. Our task was to examine the mounting evidence that many Australian species appear to show a rather shallow genetic pool from a (or several) major past bottlenecks.

What’s a ‘bottleneck’? In reference to the form after which it was named, a genetic bottleneck is the genetic diversity aftermath after a population declines to a small size and then later expands. The history of this reduction and subsequent expansion is written in the DNA, because inevitably gene ‘types’ are lost as most individuals shuffle off this mortal coil. In a way, it’s like losing a large population of people who all speak different languages – inevitably, you’d lose entire languages and the recovering population would grow out of a reduced ‘pool’ of languages, resulting in fewer overall surviving languages.

Our workshop focus started, as many scientific endeavours do, rather serendipitously. Several years ago, Jeremy Austin noticed that devils who had died out on the mainland several thousand years ago had a very low genetic diversity, as do modern-day devils surviving in Tasmania. He thought it was odd because they should have had more on the mainland given that was their principal distribution prior to Europeans arriving. He mentioned this in passing to Steve Donnellan one day and Steve announced that he had seem the same pattern in echidnas. Now, echidnas cover most of Australia’s surface, so that was equally odd. Then they decided to look at another widespread species – tiger snakes, emus, etc. – and found in many of them, the same patterns were there. Read the rest of this entry »