15 July 2017: New dates for Homo naledi and (surprise!) new dates for H. sapiens

I originally intended to write about how recent dates discovered for Homo naledi meant that it and H. sapiens, our own species, had only the narrowest window in time to cross paths, but recent finds in Morocco have put paid to that. The announcements of the two sets of dates occurred within days of each other, and demonstrate just how quickly our knowledge of early human evolution is itself evolving.

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Holotype specimen of H. naledi (Photo: Lee Roger Berger research team)

The new information for H. naledi appeared in three papers published in eLife (here, here and here) in May 2017, and provided more detail about when this newly discovered species walked the Earth, as well as announcing the discovery of a second area – the Lesedi Chamber in the Rising Star cave system about 50 km northwest of Johannesburg in South Africa – containing yet more H. naledi remains.

(For more on the first discovery, see in an earlier blog the interview I did with Elen Feuerriegel, one of the ‘underground astronauts’ involved in the recovery of the H. naledi remains in the Dinaledi Chamber).

Morphologically, the new species contained features that positioned it somewhere between the Australopithecines and the early members of our own genus, Homo; this would place it somewhere around two million years old. Confusingly, however, the bones found in the Dinaledi Chamber were still made up of hydroxylapatite, a form of calcium that takes up around 70% of the weight of human bones. Normally, fossilization results in the hydroxylapatite being replaced by minerals like silica. This suggested a more recent existence for H. naledi.

And the bones spoke true. The new papers give dates for the remains that placed it between 335,000 and 236,000 years old. Since the conservative dates for our own species up to May were 190,000 years ago, or 260,000 if you count the Florisbad skull as belonging to our own species instead of another such as H. heidelbergensis, it seemed unlikely, if remotely possible, that our ancestors crossed path with H. naledi.

But then came the second announcement.

A paper published in Nature in June 2017 revealed that H. sapiens remains discovered at a cave called Jebel Irhoud in Morocco, approximately 100km west of Marrakesh, and retrieved largely during the 1960s, have now been dated to extend as far back as 300,000 years, pushing it way beyond Florisbad and well within reach of H. naledi.

Jebel_Irhoud_1._Homo_Sapiens

Irhoud 1(Photo: Ryan Somma)

The skulls among these finds are not shaped like modern human skulls; the remains were originally classified as belonging to a sort of African Neanderthal. But the faces are flat, like our own, without the prominent inflated brow ridge of Neanderthal.

Where exactly they lie in the long line of human evolution is not known for certain, but their location and their age suggest strongly that they are archaic H. sapiens and not some other species.

While this does not change the overall pattern of human evolution as currently understood, it does dramatically extend the time that our species has existed, and strengthens the argument that the cradle of modern humanity was indeed Africa.

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14 May 2017: New story out in Review of Australian Fiction

Very pleased to announce a story written with the amazing Anna Tambour, titled ‘Joy’, has appeared in the Review of Australian Fiction.RAF

What’s more, it appears in the same issue as ‘Water Cools Not Love’, a story by another wonderful writer, Laura Goodin.

The issue can be found here.

 

 

08 May 2917: Update on Homo floresiensis

Since my last blog on Homo floresiensis almost a year ago, two new discoveries have pushed back the origin of the species to at least 700,000 years ago and clarified its line of descent.

The original remains were found in Liang Bua cave on the Indonesian island of Flores in 2004. A short hominin that stood about a metre high, almost inevitably the new species was dubbed the ‘Hobbit’.

H. floresiensis

Homo floresiensis almost certainly not descended from …

There was initial controversy in some corners about whether the remains represented a new species or diseased specimens of Homo sapiens. Mounting evidence that it was indeed a new species climaxed with the announcement in June 2016 that fossils found in the So’a Basin of central Flores in 2014 possess characteristics that are morphologically similar to those found in Liang Bua fossils.

At 700,000 years old, these new fossils are the most ancient hominin remains yet found in Flores, and strongly suggest the ancestors of H. floresiensis first reached the island long before anatomically modern humans had evolved in Africa.

The main debate subsequently shifted to whether or not H. floresiensis was descended from Homo erectus – whose fossils were first discovered in Java – or some other early hominin.

H. erectus

Home erectus, but possibly from …

If descended from H. erectus, the Hobbit was an excellent example of ‘island dwarfism’, where populations of larger animals restricted in geographical range – usually islands – decrease in size over time. (Ironically, smaller animals in the same situation, lacking predators, tend to increase in size.)

A new paper published in the Journal of Human Evolution in April this year, however, presents strong evidence that H. floresiensis most likely descended from an earlier hominin. In the words of the authors, the results of their research indicates it is ‘a long-surviving relict of an early (>1.75 Ma) hominin lineage and a hitherto unknown migration out of Africa … ’

H. habilis

Homo habilis.

Using Bayesian phylogenetic methods and ‘parsimony’, the authors conclude that H. floresiensis is sister either to H. habilis alone or to a clade consisting of other hominin species including H. erectus and H. sapiens. However, they point out that a close phylogenetic relationship between H. floresiensis and H. erectus or H. sapiens can be ruled out.

These findings are important for two reasons.

First, they should finally put paid to any theory that the Hobbits are simply pathological specimens of our own species.

Second, it suggests that our hominin ancestors were migrating from their African homeland long before Home ergaster – the probable ancestor of H. erectus and sister species – decided to emigrate to pastures new some two million years ago.

Wanderlust, it seems, is an essential part of our genetic makeup.

06 May 2017: New story out in Dreaming in the Dark anthology

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Dreaming in the Dark, ed Jack Dann, PS Publishing

My story ‘Moonshine’ has appeared in the new anthology edited by Jack Dann – Dreaming in the Dark – put out by PS Publishing.

The story was inspired by the my grandfather’s time as a bootlegger during the Prohibition in the United States.

The following is from the story’s afterword.

‘My grandfather, Chuck Chamberlain died in 1975. Massive stroke, fell into a coma and never woke. My mother and I drove up to his flat in Stockton, a northern suburb of Newcastle, and started sorting through his possessions.

‘For a man who who was born in the 19th century, lived on three continents and fought in at least one great war, he hadn’t accumulated a lot of stuff. One of the first things we discovered was an old sea chest; inside the chest, among some old clothes, was a chair leg. I picked it up, curious why my grandfather had stored it away, and noticed a cork in one end. I pulled out the cork and a collection of false ID papers and photographs and records dropped out. My mum and I checked the false ID with the photos; it was definitely her father, but under a false name – Orville C. Parr.

‘It took my mum a few years to figure out most of the story – she never got all of it – and it turns out he’d been a bootlegger during prohibition, running grog across the Canada-US border, probably driving trucks into Detroit. He got word the long arm of the law was about to tap him on the shoulder, so he joined the American army under the name of Parr and got posted to the Philippines. When his enlistment was up, he sailed to Australia.

‘I remember him as a cigar-smoking man of few words. He was born and bred in England, spoke with an American accent, and lived more than half his life in Australia. I never really knew him. Nor, as it turns out, did my mum.’

I’d like to thank Jack for taking the story and PS Publishing for backing the anthology. ‘Moonshine’ was written over many years, and it was wonderful to find such a great home for it in the company of so many amazing stories by so many amazing writers.

Dreaming in the Dark can be purchased directly from PS Publishing.

22 May 2016: Crows got smarts

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Corvus corax, the common raven. Photo: Pkspks [CC BY-SA 4.0]

It’s no secret that corvids – crows and ravens – are exceptionally smart for birds, especially at problem solving. Now an experiment carried out with ravens provides evidence they may have a basic Theory of Mind as well; this means they have an ability to attribute mental states they experience to another raven.

In a paper published in Nature in February, researchers Thomas Bugnyar, Stephan Reber and Cameron Buckner from the universities of Vienna and Houston, carried out an ingenious experiment that tested how ravens caching food behaved when they thought they were being seen by another raven.

There is increasing evidence that the Theory of Mind exists in chimpanzees, bonobos, scrub jays and ravens. How equivalent the experience of a ToM is between species is, so far, untestable, but the strong possibility that some form of ToM exists in different animals provides yet more evidence of the complexity of the mental life of species apart from humans.

Not only does this add weight to calls that humans should reconsider the way they relate to other animals, especially the often appalling way we treat farmed and domesticated animals, but firmly places Homo sapiens as the product of the same evolutionary process that produced ravens, dogs and garden slugs.

17 May 2016: ScoMo’s slowmo

Budget

Comme Sisyphe by Honore Daumier (Brooklyn Museum)

Treasurer Scott Morrison’s mantra on budget night was “Jobs and growth”.

Much of the political narrative surrounding the 2016 Budget was about creating jobs, creating pathways to jobs, filling jobs, training people for jobs. It was about jobs for the future, jobs for Australia.

It was about getting Australians back to work.

But what about getting Australia itself to work?

What about getting Australia working as one nation, one people, united by fairness and equity rather than divided by injustice and poverty?

Listening to the speeches of many of our country’s politicians, and the commentary that follows in the media, I can’t avoid the feeling they’re talking about an imaginary Australia, an Australia that exists only in an ideologically-created fantasy.

It’s an alluring fantasy, too, for many conservative Australians. It involves a world where the better angels of our nature materialise in the board rooms of the largest companies, and where paternalism – here called the “trickle-down effect” or “supply-side economics” or, more damningly, “voodoo economics” – is genuinely concerned not with self-aggrandizement but the betterment of all humanity.

But this is a world constructed from the thin and rapidly unravelling fibres of neoconservative economics, a febrile dream of a world with resources that would never run out feeding a market that would never stop growing.

This is a dream that Australia is only now slowly rousing from. We are opening our eyes and seeing what we have wrought: a broken connection between what makes a society wealthy and what makes a society liveable.

Families, particularly women and children, are increasingly worse off and dramatically vulnerable to domestic violence. Affordable housing is in short supply. For many, a world-class education is now unaffordable and world-class health care increasingly unobtainable. The majority of Australians now look forward to a retirement hindered by the threat of poverty and shortfalls in aged care. Unemployment in many parts of the country is entrenched and multi-generational.

That any of this is happening in Australia, for the size of its population one of the wealthiest countries in all history, is unbelievable.

No. Sorry. It is believable because it is happening. It is a tragedy, and a tragedy that at present has no prospect of catharsis because it does not seem the political will exists to turn things around, to realise that Australia is made of 24 million human beings rather than the companies listed on the Australian Stock Exchange.

Let me say that I’m not against business. I’m not against the accumulation of wealth and capital. I’m not against free enterprise.

What I am against is inequality and injustice. What I am against is a free enterprise system untrammelled by regulation that is both efficient and enforced, and without a system to redistribute equitably a portion of wealth so that the whole of society benefits.

Free enterprise cannot properly operate in a society that itself is not free but imprisoned by poverty and division.

The good news is that there is a solution.

First, we need to look over our shoulder.

We need to look back to the past and see how previous generations of Australians made huge sacrifices so that those who followed did not suffer from hunger, from despair or from fear, but instead inherited a nation with great promise, great ambition and great hope.

We are no longer making those sacrifices for those who come after us. We have forgotten what it is like to struggle for the generations to come instead of just for ourselves.

Second, we need to look out to the far horizon and not down at our feet. As a nation we are failing to future-proof because we have forgotten there is a future. We cannot afford political decisions made today simply to be about today, or the next news cycle, or even the next election. Every time the government chooses the short-term over the long-term, the future is diminished.

Third, investing in Australians instead of in huge companies whose management and majority shareholding live far from these shores, will make a dramatic difference, bringing benefits not just to society but to the national economy.

Fourth, politicians must not only comprehend that social justice and a healthy economy go hand-in-hand, but understand why the link exists. An IMF report from 2015 on the causes and consequences of income inequality  will provide some of that understanding. In part, the report reveals there is an inverse relationship between income accruing to the richest and economic growth. A rise of 1% point in the income share of the top 20% leads to lower GDP growth. A similar increase in the bottom 20% is associated with a higher GDP growth. A similar increase in disposable income for the middle class also leads to higher GDP growth.

As Per Capita’s Stephen Koukoulas pointed out in The Guardian, “ … the government could have aimed to reduce inequality in the economy by skewing the income tax cuts linked to low-income earners [where the] marginal propensity to spend is higher … The cost to the budget of skewing tax cuts to lower-income earners could have had the same impact on [the] bottom line but with the benefit of faster GDP growth and jobs than what is currently projected.”

In other words, Scott Morrison’s budget is a slow motion crawl to growth and jobs. The problem is, the longer we delay taking action, the more the country’s options are whittled away. The longer we delay taking action, the greater the cost and the repercussions we let fall on the shoulders of our children and their children after that. By not acting now, we are implicitly shrugging off our responsibilities as good citizens.

By not acting now, we are failing to make Australia work for all Australians.

16 May 2016: New dates for the ‘Hobbit’

Homo floresiensis

Photo: Ryan Somma

Updating my blog celebrating the 10th anniversary of the discovery of Homo floresiensis, better known as the ‘Hobbit’, a letter in Nature has revised the most recent dates for the remains from 12,000 years back to 60,000 years. The sediment layers in the cave of Liang Bua on the Indonesian island of Flores, where the remains were discovered, had not been laid evenly, leading to an initial miscalculation.

Stone artefacts attributed to H. floresiensis are dated more recently, to 50,000 years ago.

The biggest implication of the new dates is that it is now less likely that the ‘Hobbit’ coexisted at the same time as H. sapiens on Flores. Although it cannot be ruled out, the earliest dates for human occupation at Flores is 50,000 years, leaving a very narrow window of opportunity.