" We are skeptical of claims for the ability of random mutation and natural selection to account for the complexity of life. Careful examination of the evidence for Darwinian theory should be encouraged." - Dissent from Darwin

Natural selection [is used] carelessly as a mantra, as in the evidence-free “just-so stories” concocted out of thin air by mentally lazy adaptationists. (Stephen Jay Gould)

In the absence of any other proof, the thumb alone would convince me of God's existence. (Isaac newton)

Tuesday, December 11, 2012

How FISH became man

Researchers reporting in the December issue of the Cell Press journal Developmental Cell provide new evidence that the development of hands and feet occurred through the gain of new DNA elements that activate particular genes.

"First, and foremost, this finding helps us to understand the power that the modification of gene expression has on shaping our bodies," says Dr. José Luis Gómez-Skarmeta of the CSIC-Universidad Pablo de Olavide-Junta de Andalucía, in Seville, Spain. "Second, many genetic diseases are associated with a 'misshaping' of our organs during development.

In the case of genes involved in limb formation, their abnormal functionis associated with diseases such as synpolydactyly and hand-foot-genital syndrome."


 In order to understand how fins may have evolved into limbs, researchers led by Dr. Gómez-Skarmeta and his colleague Dr. Fernando Casares introduced an extra gene known to play a role in distinguishing body parts, at the tip of a zebrafish embryo's fin. Surprisingly, this led to the generation of new cartilage tissue and the reduction of fin tissue -- changes that strikingly recapitulate key aspects of land-animal limb development. This result indicates that molecular machinery capable of activating this control element was also present in the last common ancestor of finned and legged animals and is proven by its remnants in zebrafish," says Dr. Casares


StoryTeller : Dr. José Luis Gómez-Skarmeta, CSIC-Universidad Pablo de Olavide-Junta de Andalucía, Seville, Spain
Story Research: How Legs Evolved     

Wednesday, June 20, 2012

How MONKEYS LIPS learnt to talk


Monkeys smack their lips during friendly face-to-face encounters, and now a new study says that this seemingly simple behavior may be tied to human speech. 
Previously experts thought the evolutionary origins of human speech came from primate vocalizations, such as chimpanzee hoots or monkey coos. But now scientists suspect that rapid, controlled movements of the tongue, lips and jaw were more important to the emergence of speech.


 For the study,W. Tecumseh Fitch and colleagues used x-ray movies to investigate lip-smacking gestures in monkeys. Mother monkeys do this a lot with their infants, like humans going goo-goo-goo in a baby's face while playing. Fitch,and his team determined that lip-smacking is a complex behavior that requires rapid, coordinated movements of the lips, jaw, tongue and the hyoid bone.The smacks occur at a rate of about 5 cycles per second - the exact same rate as for average speed human speech. Put vocalizations and these lip smacks together and voila- the basis of speech. As our ancestors began to live closer together and to cooperate, perhaps the conditions were just right to promote this skill. It's a mystery, though, as to why monkeys never got our gift of gab. The "singing" component of speech, which requires voluntary control over the larynx, remains an evolutionary mystery too.

StoryTeller: W Tecumseh Fitch, Department of Cognitive Biology University of Vienna
Source:  Discovery News Lip Smacks of Monkeys Prelude to Speech?
Story Research :  The wrong way to understand the origin of human language

Wednesday, May 9, 2012

How BAT and WHALE echoed each other

 Though they evolved separately over millions of years in different worlds of darkness, bats and toothed whales use surprisingly similar acoustic behavior to locate, track, and capture prey using echolocation, the biological equivalent of sonar. Now a team of Danish researchers has shown that the acoustic behavior of these two types of animals while hunting is eerily similar.

Bats and toothed whales had many opportunities to evolve echolocation techniques that differ from each other, since their nearest common ancestor was incapable of echolocation.

On a purely physical basis, you would predict that whales and bats would operate at different [echolocation] rates and frequencies," Madsen says. "But instead, they operate at the same rates and frequencies." The similarities support the idea that the acoustic behavior of bats and whales may be defined by the auditory processing limitations of the mammalian brain.

Storyteller: Peter Teglberg Madsen of Aarhus University, Denmark
Source: Bats, Whales, and Bio-Sonar: New Findings About Whales’ Foraging Behavior Reveal Surprising Evolutionary Convergence

Monday, March 26, 2012

How HUMAN walked upright

An international team of researchers have discovered that human bipedalism, or walking upright, may have originated millions of years ago as an adaptation to carrying scarce, high-quality resources.

The research findings suggest that chimpanzees switch to moving on two limbs instead of four in situations where they need to monopolize a resource, usually because it may not occur in plentiful supply in their habitat, making it hard for them to predict when they will see it again. Standing on two legs allows them to carry much more at one time because it frees up their hands.

In such high-competition settings, the frequency of cases in which the chimpanzees started moving on two legs increased by a factor of four.

Storyteller:  Brian Richmond, George Washington University
Source: Humans Began Walking Upright to Carry Scarce Resources, Chimp Study Suggests

Story Research :  Design perspectives and the physiology of walking, ARN

Wednesday, February 15, 2012

How ZEBRA got her stripes

According to Gábor Horváth and his team in their  recent publication in the Journal of Experimental Biology, the zebra stripe hide pattern is the least attractive to voracious horsefiles.

According to Horváth, these insects are attracted to horizontally polarized light because reflections from water are horizontally polarized and aquatic insects use this phenomenon to identify stretches of water where they can mate and lay eggs. Blood-sucking female tabanids are also guided to victims by linearly polarized light reflected from their hides.

The team measured the stripe widths and polarization patterns of light reflected from real zebra hides and they found that the zebra's pattern correlated well with the patterns that were least attractive to horseflies.

Horváth concluded that zebras evolveded a coat pattern in which the stripes are narrow enough to ensure minimum attractiveness to tabanid flies : "The selection pressure for striped coat patterns as a response to blood-sucking dipteran parasites is probably high in this Africa."

Story Teller: Scientist Gábor Horváth and team from Hungary and Sweden
Source:  How the Zebra got its stripes

Saturday, August 27, 2011

How WHALE got his big mouth

According to the researchers an ancient jawbone showed that nature's largest mouths probably evolved to suck in large prey rather than to engulf plankton-filled water. The prehistoric jaw, was very different from modern baleen whales where the lower jaw does not fuse at the "chin". Instead there is a specialised jaw joint that allows each side of the jaw to rotate. By having two curved lower jaw bones that rotate in this way, baleen whales are able to produce huge gapes to take in massive quantities of water and prey.

Lead researcher, Erich Fitzgerald  said: "This is compelling evidence that these archaic baleen whales could not expand and rotate their lower jaws, which enables living baleen whales to engulf and expel huge volumes of seawater when filter feeding on krill and other tiny animals."

Crucially though, the fossilised whale, named Janjucetus hunderi, did have a very wide upper jaw. Dr Fitzgerald says that this widening was the earliest step in the evolution of today's whales' gigantic mouths "I was able to discover the sequence of jaw evolution from the earliest whales to the modern giants of the sea," he said. "The loose lower jaw joint that enables living baleen whales to greatly expand their mouths when filter feeding evolved later."

Storyteller : Erich Fitzgerald from the Museum Victoria in Melbourne
Source:  Fossil shows huge mouth evolution

Story Researcher: Richard Sternberg
Source: Whale Evolution Vs. Population Genetics - Richard Sternberg

Thursday, December 30, 2010

How BEE designed her nest

Females from a newly discovered "solitary" species build the perfect environment for their eggs according to scientist Jerome Rozen.

This bee makes a "petal sandwich" out of two layers of flower petals inside a small burrow it digs in the ground, cementing them together with clay or mud.   When the physical structure is ready it gather provisions of a sticky mix of nectar and pollen and places it on the chamber's floor. An egg is deposited on its surface, and the chamber is closed by carefully folding the petals at the top. The nest is capped with a plug of mud,  sealing the young bee in a humid chamber  that becomes rigid and protects the larvae as it eats its rations, spins a cocoon, and falls into a 10-month sleep until spring. 

"They've found a way of protecting this immature stage by creating an environment with fairly high humidity," Rozen said. "The humidity is high because the chamber is constructed with two layers of petals with mud in between, which means the food will not dry out when the larvae feeds. Meanwhile the outside becomes very hard like a nut. This makes it very comfortable and very safe because nothing's going to come down and crush them. Anything that wants to eat them from above is going to have a hard time. We are most intrigued by its beauty and as an evolutionary mechanism for protecting offspring".


Storyteller:   Jerome Rozen, Curator , American Museum of Natural History.

Source:  Rare Bees Make Flower-Mud "Sandwiches"

Sunday, December 5, 2010

How SNAKE got GROOVY

According to Jon Mitchell from the University of Chicago, "A SET of 200-million-year-old teeth from a beast related to dinosaurs and crocodiles has shed light on how snake fangs evolved. They support the idea that venom canals inside fangs evolved from grooves on the tooth surface."  Jon and his colleagues discovered 26 Uatchitodon teeth that  shows how grooves initially formed at the surface and gradually lengthened and deepened until they became enclosed canals. Bryan Grieg Fry from the University of Melbourne, Australia, is convinced this is the case, and says the fossil series is "fantastic".

Storyteller: Jon Mitchell, University of Chicago and Bryan Grieg Fry, University of Melbourne

Wednesday, November 3, 2010

How LEOPARD got her spots

A new study carried out by researchers at the University of Bristol studied 35 species of wild cats and concluded : "These very complex and irregular models on their fur have probably evolved to help the cats have a good camouflage. This link between environment and fur patterns is quite strong but after looking at the evolutionary history, we can see that these patterns can evolve but also disappear quite fast."

Some exceptions were however highlighted: Some cheetahs have spots even though they live in open spaces, while the bay cat and the flat-headed cat, who prefer closed habitats have plain coats. Also, out of the 35 species, only one cat has vertically elongated patterns, that have nothing to do with grasslands: the tiger. On the other hand, tigers seem to camouflage really good so why don't other animals have vertical stripes too?

This would confirm Rudyard Kipling's explanation of leopard's spots: the environment “full of trees and bushes and stripy, speckly, patchy-blatchy shadows”.

Storyteller: Will Allen, Unversity of Bristol School of Experimental Psychology

Source: How did leopards get their spots

Monday, September 6, 2010

How MOLE became a star

This weird and wonderful creature is the star-nosed mole. It relies heavily on its remarkable star-shaped nose. This organ enables the star-nosed mole to decide whether something is edible with astonishing speed. The star-shaped nose is a highly specialized sensory-motor organ, which consists of 11 pairs of fleshy finger-like 'tendrils'. The star is divided into a high resolution central fovea region and less sensitive peripheral areas. its surface is covered with 25,000 mechanoreceptors called Eimer's organs. This makes the star ultrasensitive - it is, in fact, the most sensitive organ in the entire animal kingdom.

The star-nosed mole evolved to inhabit a wetland habitat, and so was placed under selective pressure to exploit the dense populations of small insects it found in its new environment.

Storyteller: Catania, K.   Olfaction: Underwater 'sniffing' by semi-aquatic mammals.
Source:  The star-nosed mole's amazing appendages

Sunday, July 4, 2010

How the PELICAN got his beak


The identification of an extremely well preserved 30-million-year old fossilised beak raises interesting questions over why evolution has left the birds so little changed over such a long period.
The nearly complete beak of the 30-million-year old fossil, found in the Luberon area of south-eastern France, resembles those of the seven modern pelican species so closely that it falls within the genus Pelecanus.

Pelican beaks are the longest of any living birds. Beneath the beak is a flexible pouch that allows the birds to capture their prey in the water, then spit out the water before swallowing their meal. Like other bird beaks, they are rarely preserved as fossils, so little had been known about their early evolution.

Storyteller: Antoine Louchart of the University of Lyon, France.
Source: Pelican fossil poses evolutionary puzzle

Thursday, April 15, 2010

How BEETLE got his jewels

According to researchers from the University of Texas, the jewel scarab species Chrysina gloriosa can distinguish between circularly polarized and unpolarized light. That ability could provide the beetles with a tremendous advantage, the researchers say, because most of the light reflected off these beetles’ colorful bodies happens to be circularly polarized. Because ability to see CP light is very rare in nature, it’s not likely that any of the beetles’ predators can see it. So the ability to both see and reflect CP light probably evolved to allow jewel scarabs to communicate with each other while staying hidden from predators

Storyteller: Parrish Brady, University of Texas
Source: Beetles stand out using Avatar tech

Wednesday, January 27, 2010

How DOLPHIN learnt to hear

Two new studies in the January 26th issue of Current Biology, a Cell Press publication, show that bats' and whales' remarkable ability and the high-frequency hearing it depends on are shared at a much deeper level than anyone would have anticipated -- all the way down to the molecular level.

If you draw a phylogenetic tree of bats, whales, and a few other mammals based on similarities in the prestin sequence alone, the echolocating bats and whales come out together rather than with their rightful evolutionary cousins.

"We were surprised by the strength of support for convergence between these two groups of mammals and, related to this, by the sheer number of convergent changes in the coding DNA that we found," Rossiter said.

Storyteller: Stephen Rossiter of the University of London
Source: In Bats and Whales, Convergence in Echolocation Ability Runs Deep

Monday, January 4, 2010

How BIRD lost his teeth

According to scientists at the Chinese Acadamy of sciences in Beijing, the earliest birds went to extreme measures to address weight issues: they lost their teeth.

The team compared the body structure of a number of early birds and found that some toothed species were more adapted for flight. They think natural selection may have put pressure on weaker fliers to lose their teeth in a bid to improve their skills by losing excess weight. "It would be especially advantageous to reduce the weight of the head because [it] is further from the centre of gravity," they write.

That theory is "as good as any other", says Mike Benton at the University of Bristol, UK, though he remains sceptical. "Losing teeth wouldn't make a huge difference to balance in the air."

StoryTeller: Zhonghe Zhou at the Chinese Academy of Sciences in Beijing
Source: Early birds may have dropped teeth to get airborne

Sunday, November 29, 2009

How SHARK got his hammer

According to New Scientist, "It's one of evolution's most eccentric creations: a head shaped like a hammer. Now, a study suggests that the hammerhead shark may have evolved its oddly shaped snout to boost the animal's vision and hunting prowess."

For over a century, scientists have speculated why hammerheads evolved such an odd shape and whether having eyes so far apart would enhance their vision. In 1942 a leading authority on sharks, Gordon Walls, suggested the position of the shark's eyes prevented it from having binocular vision. But others have argued exactly the opposite, saying the animals must have enhanced eyesight.

Now, hammerhead sharks have had their first eye examination, and it has laid the debate to rest. Sharks with wider heads have better binocular vision – all the better to track fast-moving prey like squid with far more accuracy than sharks with close-set eyes.
The research also shows that hammerheads – among other sharks – have a 360-degree view of the world in the vertical plane, allowing them to simultaneously see prey above and below them.

Story teller: Michelle McComb of Florida Atlantic University

Wednesday, October 28, 2009

How MOLE RAT got naked

ScienceDaily - Naked mole rats are strange, ugly, nearly hairless mouse-like creatures that live in underground communities. Unlike any other mammal, these communities consist of queens and workers more reminiscent of bees than rodents
They are 3-6 inches long, have pink furless skin, tiny eyes which never see the light of day, and long front teeth for digging.

Scientists call it "eusocial" in that the young are cared for by the group, individuals in the group give up their ability to reproduce in order to do other jobs, and there are at least two generations that overlap to do the family's work, Honeycutt noted.

"Biological evolution is generally seen as a competition, a contest among individuals struggling to survive and reproduce," said Dr Rodney Honeycutt.

"It runs counter to everything we know about evolution," Honeycutt said. "In fact, (Charles) Darwin himself said social animals represent a real challenge to his theory (of natural selection and individual fitness)."

Storyteller : Dr. Rodney Honeycutt, Texas A&M Univeristy
Source: Desparate Mole-Rats

Thursday, September 24, 2009

How HUMAN controlled his urge

Lust is a universal preoccupation, one of the most compelling of the Seven Deadly Sins, new studies confirm. Whereas not only humans, but also birds and mammals, regularly engage in promiscuous, lecherous behaviour, researchers report that only people are capable of controlling such urges.

Studies at Northwestern University indicate that lust and cuckoldry are almost "compulsive" as a direct result of their impact on the brain's reward centres, which are foci of sensual interpretation. Erotic stimuli create a neurological frenzy.

Studies at Rutgers University, the State University of New York and elsewhere show infidelity and lewd behaviour in mammals and birds result from a "constellation of neural correlates." Researchers agree that lust probably evolved to generate mating behaviour among any appropriate partners.

Storyteller: Helen E. Fisher anthropology professor and human behavior researcher, Rutgers University

Friday, August 14, 2009

How SPLEEN got some respect

Scientists have discovered that the spleen, long consigned to the B-list of abdominal organs and known as much for its metaphoric as its physiological value, plays a more important role in the body’s defense system than anyone suspected.

Reporting in the current issue of the journal Science, researchers describe studies showing that the spleen is a reservoir for huge numbers of immune cells called monocytes, and that in the event of a serious trauma to the body like a heart attack, gashing wound or microbial invasion, the spleen will disgorge those monocyte multitudes into the bloodstream to tackle the crisis. “The parallel in military terms is a standing army,” said an author of the report. “You don’t want to have to recruit an entire fighting force from the ground up every time you need it.”“Often, if you come across something in the body that seems like a big deal, you think, ‘Why didn’t anybody check this before?’ ” Dr. Nahrendorf said.

“But the more you learn, the more you realize that we’re just scratching on the surface of life. We don’t know the whole story about anything.”

Storyteller: Dr Matthias Nahrendorf, Massachusetts General Hospital and Harvard Medical School

Source : Finally, the Spleen Gets Some Respect

Vestigial Organs not so useless after all, Studies find

Thursday, February 19, 2009

How PTEROSAUR learnt to FLY

A new study published February 17 in the journal PLoS One by researchers from Ohio University, College of the Holy Cross and the University of Leicester explains how balloon-like air sacs, which extended from the lungs to inside the skeleton of pterosaurs, provided an efficient breathing system for the ancient beasts. The system reduced the density of the body in pterosaurs, which in turn allowed for the evolution of the largest flying vertebrates.
"We offer a reconstruction of the breathing system in pterosaurs, one that proposes the existence of a mechanism with the same essential structure to that of modern birds — except 70 million years earlier," said study co-author Leon Claessens, an assistant professor of biology at the College of the Holy Cross

Storyteller: Leon Claessens, assistant professor of biology at the College of the Holy Cross
Source: Air-filled Bones Extended Lung Capacity And Helped Prehistoric Reptiles Take First Flight

How BEETLE got thirsty

A new study reports that seed beetles may be seeking out intimate moments not to increase their chances of becoming fertilized, but for hydration. "We were curious about the behavior of these females—males are known to inflict damage during mating, and yet the females keep going back for more," said study lead author Claudia Ursprung.

We wanted to find out whether females were getting food or drinks from the ejaculated fluid," said Ursprung, whose research appears in a recent issue of the journal Behavioral Ecology and Sociobiology. Ursprung and her colleagues kept 79 female seed beetles in enclosures for eight days. Some were given food and water, some just food, and some just water. In the absence of water but not food, females were much more likely to try breeding. Being given water, however, left the females with little appetite for sex.

The beetles probably evolved this bizarre tactic because the species lives in a dry environment, the researchers suspect. "It is kind of like a bribe for mating, a way of ensuring that the female will produce offspring," said co-author Darryl Gwynne, also at the University of Toronto.

Storyteller: Claudia Ursprung of the University of Toronto Mississauga.

Source: Love Thirsty Beetles

Tuesday, February 10, 2009

How the MOCKINGBIRD became a songwriter

Mockingbirds are the quintessential example of Darwinian evolution and were in fact Charles Darwin’s primary inspiration that led to his studies of evolution.
Evolutionary theory for some time seemed to point to the fact that mockingbird songs worked to attract mates, similar to the way a peacock’s feathers attract peahens. Mockingbirds, however, are monogamous birds, unlike peacocks, and both males and females sing the varied songs of their neighbors.
Different species of mockingbirds have purportedly mimicked everything from the songs of other birds, to machines, and even songs written by humans. Evidently, this proves that mockingbirds aren’t creatures of habit, even though the mimicry would seem to prove otherwise.
Evidently, songbirds learn their styles much in the same way a human child learns language. First, babbling, then practicing, until they are able to formulate their own songs. Most song birds stop, however, once they have perfected their song.
Mockingbirds, on the other hand, continue to learn and develop new sounds and songs through the duration of their lives, which seems to make the mockingbird a lover of learning new things. This skill makes it able to continuously adapt to its surroundings as well, which is another case of survival skills being put to the ultimate test.

Story Teller: The Berkley Daily Planet.
Source:Mockingbird Jazz: The Evolutionary Roots of Bird Song,”

Story Researcher: This post was contributed by Holly McCarthy, who writes on the subject of an online university. She invites your feedback at hollymccarthy12 at gmail dot com

Monday, January 19, 2009

How NEANDERTHAL got his big nose

LONDON: Anthropologists have suggested that Neanderthals had big noses because of the degree to which their face used to jut forward, indicating that the odd feature was a fluke of evolution, not some grand adaptation. The Neanderthal nose has been a matter of befuddlement for anthropologists, who point out that modern cold-adapted humans have narrow noses to moisten and warm air as it enters the lung, and reduce water and heat loss during exhalation. Big noses tend to be found in people whose ancestors evolved in tropical climates
, where a large nasal opening helps cool the body. But Neanderthals go against this trend, according to Tim Weaver, a palaeoanthropologist at the University of California, Davis. "They were living in the glacial environment of Europe, colder than it is today, for most of the time," he said. "So, it's sort of been an anomaly. Why do they have these wide nasal apertures?," he wondered.

Storyteller: Tim Weaver, Palaeoanthropologist, University of California,
Source: Why Neanderthals had big noses

Friday, October 10, 2008

How TURTLE got her shell

A newly identified fossil could explain one of evolution's biggest mysteries – the origin of the turtle's shell. Bone fragments from a 210-million year-old, land-dwelling reptile from New Mexico suggest that the earliest turtles didn't have much of a shell at all. Over millions of years, rows of protective armour plates gradually fused together and to the reptile's vertebrae, eventually creating a complete shell. "Turtles ultimately originated from something that looked like an armadillo," says lead author Walter Joyce.

Exactly why turtles evolved their shell remains a mystery, Joyce says. A full shell might offer added protection and stability. And the proof could be in the pudding – their body plan is the world's oldest, changing little over 200 million years. "For some reason just being a turtle is an idea that came along and just really works," he says.

Storyteller: Walter Joyce, a palaeontologist, Peabody Museum of Natural History, Connecticut
Source: Fossil reveals how the turtle got its shell

Story research: Creation evolution headlines
Source:
A turtle missing Link - Are we missing something?

Tuesday, September 30, 2008

How JELLYFISH got her sting

Jellyfish may owe thanks to a humble bacterium for their ability to sting prey. Scientists have found that one of the genes necessary for them to sting is similar to a gene in bacteria, suggesting the ancestors of jellyfish picked up the gene from microbes. The research is published this week in Current Biology.

"The result was a great surprise," says developmental biologist Nicolas Rabet of the Pierre and Marie Curie University in Paris, France, who led the team. "[This kind of] horizontal gene transfer is often neglected, and could sometimes be more important than we thought." Unlike vertical gene transfer from parent to offspring, the horizontal variety happens between organisms, or even between different species.

According to Casey Dunn , an evolutionary biologist who studies phylogenetic problems "There are other explanations for the incongruencies they see in the tree such as coevolution", but Rabet points out that that since the PGA synthase gene is approximately 1000 bases long, it is statistically unlikely to be the product of multiple distinct genes converging on the same sequence.

Storyteller: Nicolas Rabet of the Pierre and Marie Curie University in Paris, France
Source: How the Jellyfish got its sting

Story Researcher: Dave Scot, Uncommon Descent
Source: Tree of Life gets stung by JellyFish


Tuesday, September 23, 2008

How HUMAN got pregnant

Yale researchers have shown that the origin and evolution of the placenta and uterus in mammals is associated with evolutionary changes in a single regulatory protein, according to a report in Proceedings of the National Academy of Sciences.

Pregnancy is a biologically unusual situation where one organism lives and develops inside another that is genetically different. Ordinarily, the immune system identifies and destroys the dissimilar tissue as if it were a parasite. But in some early mammals, changes 'turned down' the immune system, allowing the developing embryo to grow and thrive unchallenged by the maternal immune response.

"New functions arise by using an existing tool from the gene regulatory 'toolbox' in a new or different place.

According to Yale graduate student Vincent Lynch, lead author of the study, "We are writing a different chapter. In this case the function of a major regulatory tool was altered — it is like we found a redesigned hammer."

Storyteller: Vincent Lynch, Yale graduate student

Source:Redesigned hammer that forged evolution of pregnancy in mammals found