Clipmarks | Mohir's 'evolution' clips

Massive New Object Discovered at Edge of the Solar System

Tue, 19 Aug 2008 20:35:16 GMT

clipped by: Mohir

The Oort Cloud is a spherical cloud of comets believed to lie roughly 50,000 AU, or nearly a light-year from the Sun, which places the cloud at nearly a quarter of the distance to Proxima Centauri, the nearest star to the Sun. The Kuiper belt and scattered disc, the other two known reservoirs of trans-Neptunian objects, are less than one thousandth the Oort cloud's distance. The outer extent of the Oort cloud defines the boundary of our Solar System.

Objects in the Oort cloud are largely composed of ices such as water, ammonia and methane. Astronomers believe that the matter comprising the Oort cloud formed closer to the Sun, and was scattered far out into space by the gravitational effects of the giant planets early in the Solar System's evolution.

Tags: astronomy, solar system

Arsenic-eating bacteria rewrite evolutionary history

Sat, 16 Aug 2008 13:38:03 GMT

clipped by: Mohir
clipper's remarks: Oremland's team isolated and bred these bacteria in the lab. By growing them with with arsenite as the only possible food source, the researchers showed that the bacteria can indeed thrive.
The results suggest that arsenic photosynthesis evolved at the same time, or even before, "normal" photosynthesis. Oremland says a similar mechanism might once have fuelled life on Mars or on Jupiter's moon Europa.

Clip Source: www.newscientist.com

A new kind of photosynthesis that uses arsenic instead of water to harvest light promises to rewrite evolutionary history - at least that of arsenic metabolism on Earth.

Some bacteria use arsenate - arsenic with four oxygen atoms attached - as an energy source. It was thought that this form of metabolism didn't get going until long after photosynthesis filled the atmosphere with oxygen about 2.7 billion years ago. When this happened, naturally occurring arsenite would be transformed into arsenate.

But Ronald Oremland and colleagues at the US Geological Survey in Menlo Park, California, were puzzled by the great range of arsenic-eating bacteria. If they evolved recently they must have passed the ability to metabolise arsenic to each other by lateral gene transfer, he says.

arsenic metabolism could have evolved much earlier, giving plenty of time for bacteria to diversify. Newly discovered bacteria from oxygen-free hot springs in Mono Lake, California, support this interpretation.

Tags: evolution, bacteria, arsenic

Were Ancient Viruses a Key to Human Evolution?

Fri, 01 Aug 2008 18:19:23 GMT

clipped by: Mohir
clipper's remarks: These viral fragments are fossils that reside within each of us, carrying a record that goes back millions of years. Because they no longer seem to serve a purpose or cause harm, these remnants have often been referred to as “junk DNA.” Although many of these evolutionary relics still manage to generate proteins, scientists have never found one that functions properly in humans or that could make us sick.
That is until Thierry Heidmann who runs the laboratory at the Institut Gustave Roussy, on the southern edge of Paris, brought one to life. Heidmann long suspected that if a retrovirus happens to infect a human sperm cell or egg, which is rare, and if that embryo survives—which is rarer still—the retrovirus could have the evolutionary power to influence humans as a species becoming part of the genetic blueprint, passed from mother to child, and from one generation to the next, much like a gene for eye color or asthma.

Clip Source: www.dailygalaxy.com

When the mapping of the human genome was completed in 2003, researchers discovered a shocking fact: our bodies are littered with the shards of retroviruses, fragments of the chemical code from which all genetic material is made. This discovery has created a new discipline, paleovirology, which seeks to better understand the impact of modern diseases by studying the genetic history of ancient viruses.

Highly infectious viral diseases -including the Plague, yellow fever, measles, smallpox and he Spanish Flu, which killed 50 million people at the end of the First World War, moving from one cell to the next, transforming each new host into a factory that makes even more virus. In this way, one infected cell soon becomes billion -that die when the host dies.

Endogenous retroviruses, however, once they infect the DNA of a species they become part of that species: they reside within each of us, carrying a record that goes back millions of years.

Tags: evolution, virus, dna

When Computers Meld With Our Minds

Fri, 25 Jul 2008 20:30:20 GMT

clipped by: Mohir
clipper's remarks: a worthwhile read.

Clip Source: discovermagazine.com

Is your overflowing e-mail in-box a herald of the next stage in human evolution? Those e-mails represent just a small sample of the vast amount of digital information being generated by the gigabyte every minute. If we can cope with this rising flood of information, we are likely to be on track for using technology in the creation of superhuman intelligence, according to Vernor Vinge, futurist, best-selling science fiction author, and retired professor of computer science. Machines will become far more than just tools; they will physically merge with us, seamlessly endowing powers that are currently beyond our imagination. And all of this will happen in our lifetime, Vinge says.

Tags: singularity, brain, computers, mind

Dinosaur evolutionary tree unveiled

Thu, 24 Jul 2008 12:47:29 GMT

clipped by: Mohir
clipper's remarks: It remained at that low level throughout the following Cretaceous period, a time of plenty in Earth's terrestrial history in which flowering plants, lizards, snakes, birds and mammals all became much more numerous. Dinosaurs apparently did not take advantage of the abundant food supply that emerged during the Cretaceous Terrestrial Revolution.

"Our supertree allows us to look for unusual patterns across the whole of dinosaurs for the first time," says Lloyd. "It is the most comprehensive picture ever produced of how dinosaurs evolved."

Clip Source: www.newscientist.com

Dinosaurs may have been the largest land animals of the Cretaceous period, but a new study suggests that they were conspicuously absent from the 'terrestrial revolution' of that time, in which the number of land species rose rapidly.

Graeme Lloyd at the University of Bristol, UK, and his team studied all of the existing dinosaur taxonomic literature to produce a 'supertree' of dinosaur species. The new supertree, which includes 440 of the 600 known dinosaur species, shows that the dinosaurs evolved rapidly during their first 50 million years. By the Middle to Late Jurassic, a period famous for its giant dinosaurs including Diplodocus and Allosaurus, dinosaur evolution had slowed to a crawl.

Explore the new supertree

Tags: evolution, dinosaurs

Flatfish caught evolving, thanks to its roving eye

Sun, 13 Jul 2008 18:33:06 GMT

clipped by: Mohir
clipper's remarks: Now Friedman reports finding two different missing links. They are fossil fish with their eyes in different places on the two sides of their skulls - one in the normal position and one closer to the midline (see Diagram). One is Amphistium, a previously described genus found in several fossil deposits in Europe, in which the asymmetry went unnoticed because in fish fossils only one side of the animal is generally preserve. The other is Heteronectes, a new genus. At 10 to 20 centimetres long, the specimens were clearly adults and not larvae in which the eyes were migrating

Clip Source: www.newscientist.com

THE slightly skewed faces of two fossil fish have caught the evolution of flatfish eyes in action, filling a gap in the fossil record that has plagued the theory of evolution since Darwin's day.

The asymmetric placement of flatfish eyes has long been a puzzle. Larval flatfish have their eyes on opposite sides of the skull, but when they are still tiny - around one centimetre long - one eye migrates to the opposite side so that both eyes point upwards when the fish lies on its side on the sea floor.

Clip Source: www.newscientist.com

"Both the initial and final states make sense" because they offer evolutionary advantages for swimming in open water or along the bottom, respectively, says Matt Friedman at the University of Chicago. The problem for natural selection is that intermediate forms seemed to offer no clear advantage, and no examples had been found. As such, flatfish eyes have been used to challenge Darwin's theory ever since it was published in 1859.

Tags: evolution

Will Our Future Brains Be Smaller?

Sun, 13 Jul 2008 18:12:08 GMT

clipped by: Mohir
clipper's remarks: Why does the brain need these two decision-making areas? What benefit does the new cortex bring? After all, extra brain means extra weight and energy required to carry it around. Furthermore, is the older sub-cortical system now largely redundant? If so, could we expect it to atrophy in future humans so our brains become smaller?
The results of their modelling showed that when the threat level is high, such as the risk of being attacked by a dangerous animal, it is very useful to have the fast-acting, if inaccurate, system. But when dealing with situations which don't occur very often, or complex scenarios with many conflicting cues such as social situations, the cortical system is of more use than the sub-cortical system.

Clip Source: www.sciencedaily.com

The speed at which we react to threatening situations can have life or death implications. In the more primitive past, it could have meant escaping a wild animal; today it might mean swerving to avoid a head-on car crash.

It has been thought for some years that mammals have two decision-making systems in their brains which operate at different speeds to cope with different situations. New research from the University of Bristol supports this theory and has shown that the evolutionary pressures arising from the older, faster, but less accurate, part of the brain may have shaped the more recent development of the slower-acting but more precise cortex, found in humans and higher animals.

"The fact that lizards make decisions indicates that the sub-cortical brain in humans is also likely to be used in decision-making. However, fMRI scans now reveal that parts of the outer cortex (which developed more recently in our evolutionary past) are also used when making decisions."

Tags: brain, evolution

Unintelligent Design

Thu, 03 Jul 2008 18:14:29 GMT

clipped by: Mohir
clipper's remarks: At this point, 30 years after the Nobel Laureate Daniel Kahneman and his late collaborator Amos Tversky started documenting a rash of fallacies in human reasoning, the idea that the human mind would be "perfect in His image" is as outdated (and narcissistic) as the idea that the solar system would revolve around the planet earth.
The only theory that can really make sense of these needless imperfections is Darwin's theory of natural selection, which holds that humans (and all other life forms) evolve through a blind process known as descent-with-modification, in which new life forms represent random modifications of earlier life forms -- with no central overseer to guide the process. Such a random process can, over time, lead populations of creatures to become more adapted to their environment, but it is also vulnerable to getting stuck, in the sort of good-enough-but-not-perfect solutions that mathematicians call local maxima.

Clip Source: www.huffingtonpost.com

Lost amid all the recent discussions of intelligent design -- including Louisiana Governor Bobby Jindal's decision this past Friday to sign a bill that allows teachers in his state to "supplement" classes on evolution with talk of creationism -- is one simple basic fact. The human species isn't intelligently designed.

When you get right down to it, from an engineering perspective, the design of the human mind (and for the matter the human body) is a bit of mess.

Take, for instance, human memory, and the trouble we often have in remembering even the most basic facts -- where did we put our keys? Where did we park our car? Because our brains so often blur our memories together. Human eyewitness testimony is often no match for even a low-rent survelllance camera, and memory can fail even in life-or-death circumstances. (6% of all skydiving fatalities, for instance, are from divers that forgot to pull their ripcords),

Tags: evolution, creationism, intelligent design

Counting monkeys tick off yet another 'human' ability

Tue, 01 Jul 2008 16:41:09 GMT

clipped by: Mohir

Clip Source: www.newscientist.com

[Video]

At this rate a monkey might prove the Riemann hypothesis. Rhesus macaques have been shown to possess yet another numerical talent once thought unique to humans – they can simultaneously count audible beeps and dots on a computer screen.

Their ability to comprehend numbers not as just discrete images or sounds, but as abstract representations that can be combined suggests that such maths skills aren't unique to humans, says Kerry Jordan, a psychologist at Utah State University, Logan, US, who led the new study.

This sort of evidence "shows that [animals] have these precursors to math very early on in the evolutionary line and early on in development," she says.

Tags: monkey, math, evolution, human

Mechanism and function of humor identified by new evolutionary theory

Mon, 30 Jun 2008 21:24:01 GMT

clipped by: Mohir
clipper's remarks: "By removing stipulations of content we have been forced to study the structures underlying any instance of humour, and it has become clear that it is not the content of the stimulus but the patterns underlying it that provide the potential for sources of humour. For patterns to exist it is necessary to have some form of content, but once that content exists, it is the level of the pattern at which humour operates and for which it delivers its rewards."

Previous theories have only ever applied to a small proportion of all instances of humour, many of them stipulating necessary content or social conditions either in the humour itself or around the individual experiencing it. But this doesn't explain why an individual can laugh at something when no one else around them does, nor why two people can laugh at the same stimulus for different reasons.

Clip Source: www.physorg.com

A new publication answers centuries' old questions regarding the mechanism and function of humour, identifying the reason humour is common to all human societies, its fundamental role in the evolution of homo sapiens and its continuing importance in the cognitive development of infants.

"The theory is an evolutionary and cognitive explanation of how and why any individual finds anything funny. Effectively it explains that humour occurs when the brain recognizes a pattern that surprises it, and that recognition of this sort is rewarded with the experience of the humorous response, an element of which is broadcast as laughter.

Tags: humor, evolution

The ADHD Advantage: Did the “Hyper” Gene Benefit Our Nomadic Ancestors?

Wed, 18 Jun 2008 19:22:24 GMT

clipped by: Mohir
clipper's remarks: "So, in other words, all of us with ADHD need to head back to the desert with a pack of camels loaded up with tents to really make the most of our “disorder” (how dare they call it that when it turns out it’s an evolutionary advantage unless you’re a semi-comatose couch potatoes). Of course half of us will absent-mindedly forget to bring essentials—like water—but we’ll have a lot of fun. Who’s with me?"

Clip Source: www.dailygalaxy.com

ADHA has gotten a bad rap in the 21st century, but all of us fidgety hyper-hypos may have evolved this way for good reason, say scientists. An ADHD-associated version of the human gene DRD4 was found to be linked to superior health among nomadic tribesmen. But oddly enough, it seems to be linked with malnourishment among their more settled cousins. Here is my completely unscientific explanation for why that might be the case: People who can’t sit still would be appreciated in a society that is always on the move, whereas in a sedentary population—like most of us live in today—we’re all but an unwanted annoyance. But whatever the real reason, scientists say these findings offer clues to why some of us evolved the way we did, and what that means for the future.

They found that those with the 7R allele in the nomadic population were better nourished than their non-nomadic brethren who carried 7R allele.

Tags: adhd, nomads, evolution, genetics

Can parasites influence the language we speak?

Mon, 16 Jun 2008 18:23:13 GMT

clipped by: Mohir
clipper's remarks: "These costly interactions especially come from interacting with people who do not belong to your society or group, whose immune systems are adapted for a separate set of parasites than your own," adds Fincher.
n the parasite-rich forest populations, interacting with others came with a high chance of contracting a lethal illness, making parasites an evolutionary driving force.

Clip Source: www.newscientist.com

What do parasites and mountains have in common? They both keep populations apart and drive evolution, say researchers.

In the absence of geographical barriers such as mountains and oceans, parasite "wedges" keep populations of the same species apart, say Corey Fincher and Randy Thornhill of the University of New Mexico in the US. They claim this can provide the opportunity for populations and even new languages to evolve separately.

Fincher and Thornhill say their hypothesis explains the longstanding ecological debate about why it is that biological diversity decreases as you move away from the equator and towards the poles.

"Individuals must balance the benefits with the costs of contacting other members of the same species," says Fincher. For humans interacting with each other, for example, benefits include the opportunity to mate and trade, but these come at a cost: the risk of contracting a parasite or disease.

Tags: language, parasites

Humor Shown To Be Fundamental To Our Success As A Species

Mon, 16 Jun 2008 16:57:26 GMT

clipped by: Mohir

Clip Source: www.sciencedaily.com

First universal theory of humour answers how and why we find things funny. Published June 12, The Pattern Recognition Theory of Humour by Alastair Clarke answers the centuries old question of what is humour. Clarke explains how and why we find things funny and identifies the reason humour is common to all human societies, its fundamental role in the evolution of homo sapiens and its continuing importance in the cognitive development of infants.

“For some time now it’s been assumed that a global theory of humour is impossible. This theory changes thousands of years of incorrect analyses and mini-theories that have applied to only a small proportion of instances of humour. It offers a vital answer as to why humour exists in every human society.”

Humour is not about comedy it is about a fundamental cognitive function.

“An ability to recognize patterns instantly and unconsciously has proved a fundamental weapon in the cognitive arsenal of human beings.

Tags: humor

Susan Blackmore on Memes and Temes

Wed, 04 Jun 2008 16:13:00 GMT

clipped by: Mohir
clipper's remarks: Video at source.

Clip Source: www.spring.org.uk

Charles Darwin's theory of evolution is probably the best idea that anybody has ever had. Darwin's idea is not just applicable to biology, though, it also applies to culture.

The application of natural selection to culture has been called 'memetics'. This is the theory that, like living things, ideas - or 'memes' - naturally vary and that (generally) the 'fittest' ideas survive and are replicated across generations.

Neuroscientist Susan Blackmore, who has studied memetics, introduces a new type of meme which she calls the 'teme': the technological meme. Technology, through temes, she argues, is now driving us forward, whether we like it or not.

In this talk Blackmore uses the idea of the 'teme' to pose some interesting questions. She asks whether there are other lifeforms out there in the universe and also whether humanity will survive the arrival of the 'temes'.

Tags: ted, meme, evoultion, susan blackmore, teme

Religion is a product of evolution, software suggests

Tue, 27 May 2008 14:31:51 GMT

clipped by: Mohir
clipper's remarks: Another contends that religion benefited our ancestors. Rather than being a by-product of other brain functions, it is an adaptation in its own right. In this explanation, natural selection slowly purged human populations of the non-religious.
To determine if it was possible for religion to emerge as an adaptation, Dow wrote a simple computer program that focuses on the evolutionary benefits people receive from their interactions with one another.

Clip Source: www.newscientist.com

God may work in mysterious ways, but a simple computer program may explain how religion evolved

By distilling religious belief into a genetic predisposition to pass along unverifiable information, the program predicts that religion will flourish. However, religion only takes hold if non-believers help believers out – perhaps because they are impressed by their devotion.

"If a person is willing to sacrifice for an abstract god then people feel like they are willing to sacrifice for the community," says James Dow, an evolutionary anthropologist at Oakland University in Rochester, Michigan, US, who wrote the program – called Evogod (download the code here).

Dow is by no means the first scientist to take a stab at explaining how religion emerged. Theories on the evolution of religion tend toward two camps. One argues that religion is a mental artefact, co-opted from brain functions that evolved for other tasks.

Tags: religion, human, brain