DNA study sheds new light on horse evolution

DNA study sheds new light on horse evolution
Bones of a new species of the hippidion horse, discovered in South America.

(PhysOrg.com) -- Ancient DNA retrieved from extinct horse species from around the world has challenged one of the textbook examples of evolution - the fossil record of the horse family Equidae over the past 55 million years.

The study, published today in the , involved an international team of researchers and the Australian Centre for Ancient DNA (ACAD) based at the University of Adelaide.

Only the modern horse, zebras, wild asses and donkey survive today, but many other lineages have become extinct over the last 50,000 years.

ACAD Director Professor Alan Cooper says despite an excellent of the Equidae, there are still many gaps in our evolutionary knowledge. "Our results change both the basic picture of recent equid evolution, and ideas about the number and nature of extinct species."

The study used bones from caves to identify new horse species in Eurasia and South America, and reveal that the Cape zebra, an extinct giant species from South Africa, were simply large variants of the modern Plains zebra. The Cape zebra weighed up to 400 kilograms and stood up to 150 centimetres at the shoulder blades.

"The Plains zebra group once included the famous extinct quagga, so our results confirm that this group was highly variable in both coat colour and size."

Lead author of the paper, Dr Ludovic Orlando from the University of Lyon, says the group discovered a new species of the distinct, small hippidion horse in South America.

"Previous fossil records suggested this group was part of an ancient lineage from North America but the showed these unusual forms were part of the modern radiation of equid species," Dr Orlando says.

A new species of ass was also detected on the Russian Plains and appears to be related to European fossils dating back more than 1.5 million years. Carbon dates on the bones reveal that this species was alive as recently as 50,000 years ago.

"Overall, the new genetic results suggest that we have under-estimated how much a single species can vary over time and space, and mistakenly assumed more diversity among of megafauna," Professor Cooper says.

"This has important implications for our understanding of human evolution, where a large number of species are currently recognised from a relatively fragmentary fossil record.

"It also implies that the loss of species diversity that occurred during the megafaunal extinctions at the end of the last Ice Age may not have been as extensive as previously thought.

In contrast, studies have revealed that the loss of genetic diversity in many surviving species appears to have been extremely severe," Professor Cooper says. "This has serious implications for biodiversity and the future impacts of climate change."

More information: en.wikipedia.org/wiki/Equidae

Provided by University of Adelaide (news : web)

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Dec 10, 2009
The THEORY of Evolution must itself EVOLVE!
The humans who observe it have NOT perfected OBSERVING hence the theory has Neither been thoroughly understood, perfectly applied and defined, nor completely proven. This process, like human intellect, instrumentality, and the subjects by which we come to understand evolution, need time!
Wha? Because we have been to the moon we thought we knew EVERYTHING!
Adaptive evolution WILL be proven...once WE ADAPT :-)

Dec 10, 2009
Great definition of something that doesn't exist.

A "law" is a theory that we have never found contrary evidence for.

Part of the problem is pop science reporting. We get used to seeing "Law of Gravity", when it's really "Theory of Gravity". The fact that things fall is called an observation. The mathematical description and postulates about why this happens is called a theory. When we call something a LAW in science, it's a colloquialism and not technically correct.

Dec 10, 2009
The mathematical description and postulates about why this happens is called a theory.

The unfortunate side effect of this is that the word 'theory' has a different meaning in common language than it does to scientists. This leads people to make the argument that "Oh, [insert claim] is just a theory anyway so they don't really know anything for sure." which is extremely irritating to have to explain the difference every time.

Dec 10, 2009
The mathematical description and postulates about why this happens is called a theory.

The unfortunate side effect of this is that the word 'theory' has a different meaning in common language than it does to scientists. This leads people to make the argument that "Oh, [insert claim] is just a theory anyway so they don't really know anything for sure." which is extremely irritating to have to explain the difference every time.

It is just as irritating to hear scientists state that theories are FACTS which can never be disputed.
A bit more humility from scientists would be refreshing.
If one has a proper education, the more one learns, the more one should discover how much MORE there is to learn. This leads to the unpleasant situation of discovering how ignorant one is even after years of education.


My sentiments exactly!

Scientist can get along a lo better with non-scientist if they can stay humble. Just do your job. It will all come out in the wash

Dec 10, 2009

It is just as irritating to hear scientists state that theories are FACTS which can never be disputed.

Although this does happen sometimes (what with scientists being human too, and all) most of the time it's the pop-science reportage that simplifies and editorializes.


Scientists work VERY hard to disprove theories, creationist claims notwithstanding. In science, the best way to get cred is to create a new theory; the second-best way is to disprove an existing theory; and a distant third is to confirm an existing theory. Scientists are simply not motivated to form conspiracies of that type. Of course, they're human too, thus the old saying "science advances one funeral at a time".

Dec 10, 2009
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Dec 10, 2009
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Dec 10, 2009
Scientist can get along a lo better with non-scientist if they can stay humble.

You know what else would be great? If scientifically ignorant laypeople learned to stay humble and acknowledge their ignorance, rather than insisting on flaunting it in public in a loud, obnoxious, and insulting fashion.

It never ceases to amaze me how willing some people are to mock and reject scientific findings and processes, while themselves having not a single clue (and frequently, worse: erroneous information) regarding the subject matter. As a layperson, you are liable for being played like a political sock puppet; you are fed information that you have no background or skills necessary to judge or interpret, then you're told what conclusion to jump to. They say jump, and you ask how high. You're nothing but a tool and a dupe. Pathetic.

That's really all I want to say on the topic; I try not to feed the trolls.

Dec 10, 2009
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Dec 10, 2009
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Dec 11, 2009
But industry in the EU is 'directed' by the state via regulations, tax 'incentives', etc. It is call Fascism.

No, Fascism is when the industry runs the government, dominates labor, deliberately whips up nativist/nationalist frenzy, self-regulates, sets foreign policy, and writes the laws (all of which are the case with USA.) Fascism values efficiency over humanity.

In Europe, generally speaking it's more a case of moderate Socialism (with some variability across the different countries, of course.)

But help me out here: what does any of this have to do with horse evolution?

Dec 13, 2009
I wonder how long and hard the denialists had to dig, and how many people they had to pay off, in order to turn a couple of offhand private comments into a tempest in a teapot? Unlike scientists who are *not* generally inately motivated (in principle) one way or the other on AGW, the denialists have a very specific financial interest in AGW not being true. So feel free to attempt demonization all you want. You've got a very large hill to climb before you even get to a level playing field.

My, but you have severely misunderstood the ramifications of the data leaked, haven't you? You need to get your hands on the data and look it all over for yourself. The emails are nothing compared to some of the other material. You have people fraudulently plugging in numbers that do not exist, encouraging destruction of data, members of experts panels accusing the IPCC of using fraudulent data in their reports, data contradicting AGW censored and unpublished, and much, much more.

Dec 14, 2009

I don't think the business owners in Germany of the 20s and 30s thought they were running the government.

See frajo's response for a partial listing of German mega-corps that were running the government and profiteering from the wars. Volkswagen was started by Hitler, by the way; did you know that?

The state should retain supervision and each property owner should consider himself appointed by the state.

That may indeed be considered a Socialist item on the agenda. Of course, it's also the same stance that had been practiced in every Monarchy since time immemorial. However, this is only a rather tangential component of an otherwise corporate-run state. Nazis are like Socialists in the same way that men are like mice. For instance, Socialists tend not to hate Communists to a point of considering them enemies of the state and traitors to the nation. (Look up Hitler's views on Communism...)

Dec 14, 2009
Doesn't sound like much of a free market. Sound more like the corporate states of Europe and the USA.

My point exactly. There is no such thing as a real free market: it's a dynamically unstable system that, if actually ever tried in practice, will rapidly and spontaneously transform into something else. Any market allowed to run unsupervised (i.e. "free") will inevitably get hijacked and become controlled by a cartel of key large players (or industries.) For instance, USA has become the world capital of fraudulent finance. That's not coincidental; it's a direct consequence of our government being for sale to the highest bidder, and the consequent push for "deregulation" and "free trade". Now our "free markets" (as well as our government) are run and controlled by the likes of Goldman Sachs and JP Morgan.

Dec 14, 2009

Actually they're completely controlled by our Democrat Congress at the moment.

You have it backwards. What you have to examine, is who controls the Democrats. As well as the Republicans. You will find that our biggest industries are really the ones in control, and you will find that most of our legislation is written, vetted, and/or edited by industry lobbyists.

Dec 14, 2009
I doubt any company would willingly give up control to any dictator.

What makes a company so different from the men/women who run it? If men/women willingly give up control to dictators, then so do companies. Indeed, it's easier for companies because they are not motivated by any particular ideals or ideology: their only concern is making money, so if you are in a position to corner a market with the help of a dictator, or if you're in a position to benefit from sweetheart government contracts and various forms of pork, then you are not going to resist such money-making opportunity; on the contrary, you're going to welcome it with open arms.

Dec 14, 2009
I'm *trying* to explain to you how things work in the real world. Your idealized ideology simply cannot and does not apply. No matter how long and how hard you rave about your particular utopia, it will never come to pass in reality: because it is impossible.

As for what I support or don't support, you are presuming too much.

Dec 15, 2009
If you don't support liberty, they you must oppose it.

Only a Sith deals in absolutes.

Dec 15, 2009
"What the mind of man can conceive and believe, the mind of man can achieve."

How does that apply to utopias? Shall we try Communism one more time?

If you don't support liberty, they you must oppose it.

How do you support "liberty" without rule of law and a fair playing field? In absence of regulation, you will have neither: guaranteed. So in allowing a corporate mafia takeover of society, you in fact not only fail to support liberty -- you stand in direct opposition to it.

Funny, isn't it, how good intentions so frequently pave the road to hell?

Dec 15, 2009
One man's liberty is the other man's suppression. Societies need to balance individual liberties between the needy and the greedy.

No one has the liberty to commit violence against another or violate another's property rights.

Let's say in a given country, a given person owns 99% of all the land, which he keeps to himself and passes on to his descendants, in perpetuity. The rest of the population are relegated to the remaining 1%. Highly hypothetical, I know: however, in this thought experiment, do property rights protect liberty or impede it? In other words, at what point (if any) do the needs of the many outweigh the needs of the few?

More to the point, is grossly inequitable distribution of resources sustainable, or will it instead lead to social instability and revolution? Keep in mind that actual revolutions have undeniably happened: witness France, Russia, Cuba, China, etc, etc, etc...

Dec 16, 2009
Chill out Velanarris, I get comments periodically removed too -- for no apparent good reason (the usual justification given is "VERBIAGE".)

They're not partisan; they're just unintelligent.

Dec 16, 2009
What if all the land is supposedly held in common by all as was the USSR or Cuba? Where is the incentive to use resources most efficiently?

That's not the point. The point is that balance is vital. Property rights do not by themselves achieve balanced distribution of resources. Quite to the contrary, on their own they tend to uphold and reinforce (i.e. amplify over time) an unfair distribution.

If one individual owns all the land, how will he eat? He can farm it himself or hire someone to help. How will he pay his workers?

Have you ever encountered the subjects of Feudalism and Serfdom in your grade school world history curriculum?

Dec 16, 2009
Who decides what is the 'balance'? The mob? A dictator?

In a Democracy, that would be the Majority.

Where did the serfs go?

They were slowly elevated to the Middle Class, thanks to labor organization and Socialist policies (though in quite a few unfortunate countries, things were too far gone and a bloody revolution occurred instead.)

If you read The Road to Serfdom, we are all becoming serfs to the state. What balance!

If you checked the trends in income inequality, you would note that it has been steadily escalating since the early '80s -- precisely when Reagan launched the "free market" neocon adventure. If this continues unabated, then our country will arrive at a point of such tremendous social imbalance and malaise, that another revolution will become increasingly likely.

Dec 16, 2009
Much of that "growth" has been a debt-fueled fraud (there's a reason why Bush Sr. referred to Reagan's policies as "voodoo economics".) For example, see here what's been happening since 1980:


The whole world (with USA in the lead) is about to go bankrupt as a result. The newfangled "freedom" has sucked most productive enterprise (i.e. manufacturing) out of U.S. into the third world. As a result, formerly rural peasants are now toiling in horrid conditions for $2/day, while the environment around them gets poisoned and destroyed -- so we can have our cheap toys on credit, for as long as credit growth will last (which it can't any more, as it has just last year hit the brick wall of non-sustainability.)

I'm sorry, but the sum total of global Ponzi finance is about to blow up in all our faces. Many a Cassandra has warned of this over the years. A true Greek Tragedy in the making.

Dec 16, 2009
Oh, and by the way: we're now so far off topic, that I'm just going to stop posting here. If you want to continue the discussion, marjon, feel free to PM me.

Dec 16, 2009
Ok, I can't resist... One more post and that's it. On the diagram I linked for you, here it is again:


Notice that the government portion of the debt (both Federal and State) has been historically only a small percentage of the overall debt (most of which was incurred by companies and individuals: i.e. on the "free market".) Even now, that government is trying to fill in the gaping hole left by collapsing spending by all other parties, its share of the total debt has yet to reach even 25%.

And those debt figures, by the way, don't even include the derivatives, which have leveraged the $50 Trillion into some god-awful global number ranging into $Quadrillions -- all of it done entirely via "financial innovation" in the unregulated "free markets".

"Financial innovation" is just the New Age name for "Ponzi finance."

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