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Who Lies Sleeping? Home

25 May 2009, 11:54 pm Sticky post

There have been ages when other things ruled on the earth, and they had great stone cities. Remains are rarely, but still to be, found as cyclopean stones scarcely recognisable as constructions. Their builders all died vast epochs of time before man came, but there were conditions which could revive them when the cycle of being turned once more into the correct quadrant, when their successors proved to their makers that they had forsaken all responsibility for their tenancy as guardians of the earth.

Book Cover: Who Lies Sleeping?

Book Cover: Who Lies Sleeping?

And so it is not to be thought, that man is either the oldest or the last of earth’s masters. His predecessors wait—not in the world we know but at its edges. They rest asleep—tranquil, elemental and—except when they stir—unseen. For, after the Helliconian Spring of love and lust, the son-lover begins to sere the earth and the serpent is yet poised, motionless but alert, for its the moment to strike.

It is the serpent that conquers and enjoys the fruits of the tree of life. Must it ever be so?

These posts cover the content of the whole book plus supplementary pages and additional evidence. It begins here: Start.

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Evolution of Live Births Seen in Egg Layers!

6 September 2010, 12:50 pm
[caption id="attachment_3599" align="aligncenter" width="240" caption="Yellow Bellied Three Toed Skink"]Yellow Bellied Three Toed Skink[/caption]

The yellow bellied, three toed skink (Saiphos equalis) resembles a small snake, but with miniature legs. It reaches a length of about 18 cm, and is mostly nocturnal, feeding on insects. Biologist, James Stewart, of East Tennessee State University, et al, (Journal of Morphology), have been studying the skink and have found it is one of only three reptiles known to have different methods of reproduction in different places.

In the coastal areas of New South Wales (NSW), near Sydney, Australia, the skink lays eggs, while in the northern highlands of NSW, it tends to favor giving birth to live young. It appears the live bearers evolved from these “intermediate” skinks that retain their eggs internally longer than others. Scientists say we are witnessing evolution in action, with the skink half way in its transformation from an egg layer to a bearer of live young.

As they retain their young internally for longer, the thickness of the eggshell is reduced until, for those bearing live young, the shell is merely a thick membrane. Having a thinner shell enables the mother to keep the embryo well fed while the egg is inside her body, but there is less calcium available for the embryo. Stewart and the team found that the uterus in the egg layers secreted calcium that became incorporated into the embryo. Stewart said:

It’s basically the early stages of the evolution of a placenta in reptiles.

Giving birth to live young is an advantage in colder areas, such as the northern highlands of NSW, since the embryo develops for longer within a warm body. The negative side is that keeping the fetus in the uterus is more physically demanding on the mother. In warmer areas such as coastal regions of NSW, eggs have a better chance of surviving the climate, but the negative is a greater vulnerability to attack from predators.

Live birth is known to have evolved 132 times among animals with a backbone, 98 of these in reptiles, which suggests that, while it seems a complex transition, it might be much simpler in some cases than scientists thought. Two other species of reptiles are known to use both types of reproduction—a European lizard and another species of skink.

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The Antarctic Continent

30 August 2010, 9:00 pm

The cooling of the oceans as Antarctica passes over the South Pole has brought the risk of a freeze up within the bounds of possibility. Before about seven million years ago it was impossible. The earth’s heat store is the ocean and the heat stored in the warm surface waters until then easily caused sufficient evaporation to put plenty of latent heat into the upper atmosphere. With warm oceans there is no chance that ice crystal formation could occur in the skies and therefore heat from the sun gets to the surface of the oceans, keeping it warm. It is a positive feedback system.

But once ocean temperatures drop so much that the threshold of ice formation is crossed a new feedback system starts to operate. Ice crystals in the upper atmosphere spread to lower latitudes cutting down the sunlight and cooling the oceans even more. Evaporation reduces further still and the ice crystals become more permanent. The land cools quickly and snow gradually builds up to form an icecap. When it is sufficiently large, glaciers start to calf into the sea, again cooling it and reducing the earth’s store of heat. There is less evaporation, less latent heat transfer, more ice crystals form, less sunlight penetrates—a new feedback system locked into ice age has arrived.

Today the oceans of the world have a heat store of about ten years of sunlight. If the light of the sun were cut down for ten years it could switch on an ice age. Fine dust in the upper atmosphere could do it. It would mimic the action of the ice crystals, reflecting solar heat away from the surface of the earth. Fine dust of diameter less than a thousandth of a millimeter will stay in the stratosphere for long periods, certainly for a year but possibly for a decade or more depending upon the amount, its height and its size, and may be carried for hundreds or thousands of miles. The explosion of Thera in the Aegean Sea in 1500 BC carried dust to Egypt causing some of the plagues of Pharaoh at the time of Joseph, according to biblical myth. Very fine particles could stay aloft for a very long time indeed and, though they are not in themselves as effective as reflectors of heat as coarser ash or ice crystals, they can act as nuclei for ice crystals to condense upon.

The greatest volcanic explosion in the last two million years was the eruption of Toba in Sumatra 73,000 years ago. It was a hundred times bigger than the eruption of Krakatoa, throwing 500 cubic miles (2000 km^3) of dust into the air and creating a crater 25 miles (40 km) in diameter. Changes in the pollen in European sediments from this time show a marked cooling followed by a period of erratic weather and, after a delay of a thousand years, an ice age. This enormous eruption eventually triggered an ice age—but it failed to cause a mass extinction!

What then of Late Cretaceous times? Although a world wide drop in temperature did occur, there is no evidence of even a short ice age when the dinosaurs became extinct. As far as we know there were no icecaps, no calving glaciers and the oceans were warm. A Cretaceous freeze up did not occur because no highlands or landlocked seas were sufficiently near to the poles. Furthermore the heat capacity of the oceans was greater than it is now because little water was locked up as ice and sea levels were higher. The higher temperature and greater heat store in the oceans provided a greater safety margin over the possibility of an ice age starting. Instead of only ten years, 50 years or more of darkness would have been needed to trigger an ice age. Only in the last seven million years has the threshold of climatic instability been crossed which permitted the recent ice ages.

Originally posted 2009-06-19 22:01:31. Republished by Blog Post Promoter

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‘Stocky dragon’ dinosaur terrorized Late Cretaceous Europe

30 August 2010, 9:00 pm
[caption id="" align="aligncenter" width="400" caption="The skeletal anatomy of Balaur bondoc, a strange predatory dinosaur from Europe's Late Cretaceous."]The skeletal anatomy of Balaur bondoc.[/caption]

Paleontologists have discovered that tells us what Late Cretaceous predatory dinosaurs in Europe looked like. It was Balaur bondoc, “stocky dragon”, the size of an oversized turkey! Mark Norell, chair of the Division of Paleontology at the American Museum of Natural History and one of the authors of the research paper describing the fossil, says:

B bondoc is heavy, with unexpectedly stocky limbs and fused bones.

It was unearthed in Romania by geologist and co-author Mátyás Vremir of the Transylvanian Museum Society. It is the first reasonably complete skeleton of a meat eating dinosaur from the final 60 million years of the Age of Dinosaurs in Europe and shows an ecosystem much different from that of today. Balaur bondoc was a double clawed and unusual raptor, a close relative of Velociraptor, which hunted the dwarfed inhabitants of Late Cretaceous Europe.

[caption id="" align="aligncenter" width="400" caption="The fossilized hindlimb of Balaur bondoc showing the double sickle claws of the foot"]The fossilized hindlimb showing the double sickle claws of the foot[/caption]

Europe was an island archipelago at the end of the Cretaceous, a time of high sea levels, which flooded much of present day continental Europe, so Romania, which was an island, is now one of the best windows into Europe at the end of the Age of Dinosaurs. Fossils discovered in these deposits illustrate the “island effect” which is that island dwellers tend to be smaller than relatives on continental land masses. They include dwarf sauropods that were the size of cows and tiny duck billed dinosaurs. Animals restricted to islands are also subject to less evolutionary competition than their mainland relatives, so often stay more primitive. This island world was indeed dominated by animals smaller and more primitive than their relatives living on continents.

The new theropod fossil, the type specimen, is a partial skeleton that includes leg, hip, backbone, arms, hand, rib, and tail bones. But B bondoc has 20 unique features when compared to its nearest relatives, including a re-evolved functional big toe with a large claw that can be hyperextended, presumably used to slash prey. Because there is also a large claw on the second toe, as is typical of the group of dinosaurs to which B bondoc belongs, the new species has unusual double clawed feet. Unique features are also found in other parts of the foot, leg, and pelvis. The feet and legs are short and stocky, with bones fused together, and the pelvis has enormous muscle attachment areas, indicating that this species was adapted for strength over speed. Finally, the hand is atrophied and some of the bones are fused, features that would have made grasping difficult. This, in combination with the leg and foot traits, indicates that the lower limbs rather than hands were used to grasp and disembowel prey.

Co-author Zoltán Csiki of the University of Bucharest adds:

Balaur is unlike what we know of the large predators from other parts of the world at the same time period, like Tyrannosaurus or Carnotaurus. As European dinosaur faunas were known to be peculiar, we half-expected to find peculiar predators as well. But, as the first good record of these, Balaur surely exceeds our most daring expectations. Balaur might be one of the largest predators in this ecosystem because not even a big tooth has been found in Romania after over a hundred years of research. Fragmentary remains of Balaur were already known for more than 10 years, but the morphology is so weird we didn’t have any idea where to fit them.

Stephen Brusatte, a graduate student at Columbia University who is affiliated with the Museum says:

Balaur is a new breed of predatory dinosaur, very different from anything we have ever known. Its anatomy shows that it probably hunted in a different way than its less stocky relatives. Compared to Velociraptor, Balaur was probably more of a kickboxer than a sprinter, and it might have been able to take down larger animals than itself, as many carnivores do today.

But while B bondoc has unique features expected from the island effect, its relationship with other dromaeosaurs shows that there was some faunal exchange between the Romanian island that the mainland, at least among the carnivorous dinosaurs. Norell says:

Because Balaur is related to dinosaurs like Velociraptor, it indicates that the European island archipelago had a faunal connection with other parts of Europe, Asia and North America where this group of dinosaurs has also been found in similarly aged rocks. It also shows how pervasive island effects can be in producing truly unusual animals.
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First clear evidence of feasting in early humans

30 August 2010, 9:00 pm
[caption id="" align="aligncenter" width="400" caption="Two wild cattle lumbar vertebrae consumed as part of a feast are under excavation in Structure B at Hilazon Tachtit Cave, Israel. Credit: Natalie Munro"]Two wild cattle lumbar vertebrae consumed as part of a feast [/caption]
Scientists have speculated that feasting began before the Neolithic period, which starts about 11.5 thousand years ago. This is the first solid evidence that supports the idea that communal feasts were already occurring—perhaps with some frequency—at the beginnings of the transition to agriculture.

So says Natalie Munro of the University of Connecticut, author of new findings at a burial cave in the Galilee region of northern Israel dated about 12,000 years ago. Community feasting is one of the most universal and important social behaviors found among humans. These remains are the first archaeological verification that human feasting began before the advent of agriculture.

[caption id="" align="aligncenter" width="400" caption="Excavation area at Hilazon Tachtit Cave, Israel. Credit: Naftali Hilger"]Excavation area at Hilazon Tachtit Cave, Israel[/caption]

Munro and her colleague Leore Grosman of Hebrew University in Jerusalem uncovered the remains of at least 71 tortoises and three wild cattle, an unusually high density for the period. The tortoise shells and cattle bones showed signs of being cooked and torn apart, suggesting the animals had been butchered for human consumption. The meat from the tortoises alone could have fed about 35 people, but many more possibly attended the feast.

The finds were in two specifically crafted hollows, each made for a ritual human burial and related feasting activities. The tortoise shells were situated under, around and on top of the remains of a ritually buried shaman, which suggests that the feast occurred concurrently with the ritual burial.

[caption id="" align="aligncenter" width="400" caption="Articulated tortoise carapaces in the grave of a unique woman. The grave contained the remains of at least 71 tortoises consumed by humans as part of a burial feast. Credit: Natalie Munro"]Articulated tortoise carapaces[/caption]

A major reason why humans began feasting—and later began to cultivate their own foods—is because faster human population growth had begun to crowd their landscape. In earlier periods of the Stone Age, small family groups were on the move to find new sources of food, but around the time of this feast that lifestyle had become much more difficult. When a once nomadic group of humans settled down, it put pressure on the local resources. Munroe explained:

These public events served as community building opportunities, which helped to relieve tensions and solidify social relationships… The appearance of these feasts at the beginnings of agriculture is particularly interesting because people are starting to experiment with domestication and cultivation.

People around the time of this feast were intensively using the plants and animals that their descendants later domesticated. The combination of increased social interaction and changes in resources is what eventually led to the beginnings of agriculture.

Taken together, community integration and the changes in economics were happening at the very beginning when incipient cultivation was getting going. These kinds of social changes are the beginnings of significant changes in human social complexity that lead into the beginning of the agricultural transition.
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Dinosaurs Destroyed by Multiple Asteroid Impacts and Vulcanism

29 August 2010, 11:25 pm

An Asteroid Impact

An Asteroid Impact

The theory of a meteor impact killing off the dinosaurs was not quite right. The discovery of a second impact crater suggests that the dinosaurs were driven to extinction by several impacts rather than a single strike.

Proposed in 1980, the theory that a meteorite impact killed off the dinosaurs was controversial until the discovery of the huge Chicxulub crater in the Gulf of Mexico was the evidence of the event that doomed the dinosaurs—“the smoking gun”. An asteroid around six miles wide slammed into what is today the Yucatan Peninsula. The heat of its passage through the air and the high energy impact caused widespread fires, converted nitrogen and oxygen in the air into nitric acid which fell as rain, covered the earth with dust clouds lowering the temperature and preventing photosynthesis, the base of all food chains, and poisoned the planet with heavy metals. It was pollution and climate change such as the earth has rarely seen but that we have been causing at an accelerating rate in the last few centuries.

Now professor David Jolley of Aberdeen University says his team has uncovered evidence for a second impact in the Ukraine. The Boltysh Crater in Ukraine, measuring just 24 kilometers (15 miles) in diameter, was first reported in 2002, but until now it was uncertain how the timing of this event related to the Chicxulub impact. The new study shows it was the first of two impacts, but was several thousand years earlier. In itself, it was too small an event to have brought on a mass extinction.

Evidence from later layers of sediments that filled the crater match the Gulf of Mexico impact. Professor Simon Kelley of the Open University, who was co-author on the study, said:

We interpret this second layer as the aftermath of the Chicxulub impact.

The pollen and spores of fossil plants in the layers of mud that infilled the crater showed that soon after the impact, ferns, which can quickly recover after such devastation, colonized the devastated landscape. “Fern spikes”, strata unusually full of fern spores, often mark past devastation, but the scientists found an unexpected second “fern spike” in a layer one metre above the first—corresponding to about 5000 years—suggesting another later devastation, but both are close in age to the time when the dinosaurs went extinct.

It suggests two impacts fairly simultaneous in geographic timescales, but the Boltysh and Chicxulub impacts did not happen at the same time. So, the dinosaurs were wiped out 65 million years ago by at least two meteorite impacts, rather than a single strike. Such big asteroid impacts are rare. Even the smaller Ukrainian meteorite should only hit Earth about once every million years, but the Boltysh meteor hit the planet less than 5,000 years before the huge Chicxulub impact, the length of time between the two fern spikes. Two such rare events so close together suggests the two asteroids were somehow connected, and the most likely possibility is that they were two of a group of them, perhaps displaced by some near collison elsewhere in the solar system. So, there could have been more such strikes. Kelley says:

It is quite possible that in the future we will find evidence for more impact events.

Rather than being wiped out by one or even two impacts, the dinosaurs may have fallen victim to a succession of meteorites showering down over several thousands of years. The dinosaurs could have died out 65 million years ago because the Earth was bombarded by meteorites. What led to this bombardment is unknown. Professor Monica Grady, a meteorite expert at the Open University not involved in the new study, said:

One possibility might be the collision of Near Earth Objects.

Nasa has a program to monitor such Near Earth Objects to warn of possible future collisions.

The Deccan Traps in south central India are where vast fields of lava welled up at about the same time as the two impacts. These floods of molten rock cover 200,000 square miles and can be two miles thick. They have always been considered to be volcanic in origin. The formation of the Deccan Traps could have released so much sulphurous gas that it is another candidate for causing the mass extinction at the time, without the help of the asteroid strikes, by choking animals and preventing photosynthesis. Evidence from the Bay of Bengal suggests that a series of monumental volcanic eruptions wiped out the dinosaurs.

The largest of the massive Deccan Traps volcanic eruptions in west-central India sent basalt lava east across the continent and into the sea. There, near the town of Rajahmundry, an international team of geologists has found marine fossils deposited immediately on top of the largest ancient lava flow there. The fossils, which match those found elsewhere, are believed to be species that evolved just after the Cretaceous-Tertiary (KT) mass extinction 65.5 million years ago. Geologist Gerta Keller, of Princeton University, explained:

We went to the Rajahmundry area because volcanic layers, called traps… are found in this area interbedded in shallow marine sediments that contain microfossils, which yield age control.

There are actually two traps at Rajahmundry, each containing up to four individual pulses of lava. The lower trap represents 80 percent of the Deccan eruption. Thirty feet higher, above the fossilized remnants of a quiet shallow sea, the upper trap marks the finale of the entire volcanic episode, which came some 280,000 years after the mass extinction event. The discovery confirms two important things.

  1. the most massive Deccan eruption and the KT mass extinction happened at the same time
  2. the later, final eruption is timed right to have slowed the recovery of many living things.

The matter of the slow recovery from the meteorite impacts has long been a mystery to paleontologists. The Deccan Traps are the largest known eruptions on the surface of the Earth, and released enough greenhouse gases into the atmosphere to have caused rapid climate change.

Asteroid Impact

An Asteroid Impact

Moreover, nearby is yet another possible crater, a strange and monstrous one. It is the Shiva basin in the Indian ocean off the west coast of the peninsula, a 500 km (311 miles) wide roughly circular gouge with a central underwater peak described as the size of Mt McKinley. Strata dating to the time of the demise of the dinosaurs, 65 million years ago, are rich in iridium. Sankar Chatterjee of Texas Tech University suspects this crater was made by another, even bigger, asteroid impact. If so, it would be the largest crater found on Earth, the scar left by an asteroid several times bigger than the one that caused the Chicxulub crater. The bedrock that lines Shiva is rich in mantle rocks, as though Earth’s crust was punctured across a wide area. Where it reaches the shore, the land is shattered and riddled with faults and geothermal hot springs. The Deccan Traps overlap the eastern edge of Shiva. Were the two events related? Perhaps the Shiva event caused the vulcanism that made the Deccan Traps. Did one, or both contribute to the mass extinction that followed? And what about the Chicxulub impact basin in Mexico, which has already been blamed as the dinosaurs’ killer?

One counter argument is that it should have ejected molten rock to be dropped nearby, and still apparent. Near the Chicxulub crater, the pile of melted rock is several feet thick. No such ejecta has been found near Shiva, but perhaps some of it is below the sea, or below the Deccan Traps! Maybe the Shiva asteroid punctured the earth’s mantle causing the upwelling of lava, or maybe the Chicxulub strike sent a huge shock wave through the earth and set off the volcanic eruption that released all the lava to form the Deccan Traps. Chatterjee admitted:

The idea of Shiva as an impact basin is still very speculative, but it tends to explain so many things.

Chatterjee thinks the Chicxulub asteroid and Shiva would have to combine, perhaps with the Deccan Traps eruptions, to induce the global extinction of the dinosaurs. Dinosaurs were resilient animals that had reigned supreme in the world for 150 million years keeping the mammals that lived alongside them confined to little rat like animals scurrying around the feet of the giants, and hunted by the small raptors. Dinosaurs had the genetic variety to overcome previous disasters, but here was one that was too much for them. Not just the one Chicxulub impact but several, in a geologically rapid sequence, may have been needed to destroy them, and devastating vulcanism brought on by the impacts, extended the agony long enough to effect the extinction.

As yet, though, Shiva is not certainly an impact crater, so the idea has been met with skepticism. Some American paleontologists prefer to keep the notion of the cause of megadeath confined to the American continent. But once Shiva is shown to be an impact crater, they will have to consider the compound theory more seriously.

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Classic Maya history is embedded in commoners’ homes

25 August 2010, 7:00 pm

Maya in the Classic period (250-900 AD) regularly “terminated” their homes, razing the walls, burning the floors and placing artifacts and sometimes human remains on top before burning them again. Evidence suggests these rituals occurred every 40 or 50 years and likely marked important dates in the Maya calendar. After termination, the family built a new home on the old foundation, using broken and whole vessels, colorful fragments, animal bones and rocks to mark important areas and to provide ballast for a new plaster floor. Lucero said:

Maya royals recorded their history in writing and in imagery carved on monuments. But the commoners had their own way of recording their own history, not only their history as a family but also their place in the cosmos. These things are buried, not to be seen, but it doesn’t mean people forgot about them. They are burying people in the exact same spot and removing bones from earlier ancestors to place them somewhere else, or removing pieces of them and keeping the pieces as mementos.

This “de-animation” and reanimation of the home marked the passage of time and the cyclical nature of life. Anthropologists have known for decades about such rituals, but Lucero chose to look more closely at how the arrangement, color and condition of the buried artifacts lent them their symbolic meaning.

She and her crew found about a dozen human remains in the two homes they excavated in a small Maya center called Saturday Creek, in central Belize. These homes were occupied from about 450 to 1150 AD. Burial in the home was common among the Maya, but only a few family members were entombed there. No Maya cemeteries or other burial sites have been found to account for the rest of the dead. There is no evidence that high status individuals were specifically selected for burial in the home. It is more likely that family members who died on or near important dates were placed there during the termination and reanimation rituals, Lucero said.

The team found full or partial skeletons of men, women and children, with artifacts arranged around and even on top of the bodies. Some bodies lay flat. Others were in a sitting position, which may have signified a higher status, Lucero said. Some of the bodies had had bones removed—most often the spine and the pelvis. Black is the color of the west, death and the underworld, but Lucero never found black objects in or near a burial.

The Maya believed in a cyclical way of living. So to their way of thinking, people don’t die as much as become ancestors.

Classic Maya history is embedded in commoners’ homes

The torso and pelvis of this body, found in the floor of one of the homes Lucero excavated, had been removed. A matate and mano, used for grinding corn, were found near the right knee. A deer antler and pink quartzite stone were buried beneath the chest area.

Colors, such as red, which represented the east, life and rebirth, were commonly used in burials. Sometimes an unbroken red vessel was inverted over a skull or kneecap. Red items were generally found on the east side of the body or group of artifacts. Other artifacts—including groups of obsidian or chert rocks—represented the Maya belief in the nine levels of the underworld or the 13 levels of heaven.

Vessels were a significant part of the dedication rites. Lucero found bowls and jars that were in perfect condition when they were buried, she thought made specifically for the occasion. For termination rites, archaeologists also found used vessels with their rims broken off, jars lacking bases or necks, and vessels stacked in groups of three. Some bowls were placed lip to lip, with stores of organic matter—a food offering perhaps—inside. Other vessels were damaged with a “kill hole” drilled through their bottoms. Lucero said:

Things that were used in life had to be de-animated, terminated, before they entered the next stage of their life history.

Pieces were likely given away or placed in other sacred sites, such as caves. The rimless vessels were intriguing. Other studies have found broken, but nearly complete vessels at temple sites, with the missing pieces located in nearby homes.

Breaking off the rims is a lot of work. Removing the rims may have been a way of de-animating them as well as giving a piece to somebody else.

Perhaps the Maya revered the fragments of vessels or the bones of their ancestors in the same way that people today hold onto to, and cherish, religious relics.

The new analysis supports her hypothesis that many of the elaborate rituals performed by Maya rulers and elites had a basis in the domestic rituals of their subjects. She argued in her 2006 book, Water and Ritual: The Rise and Fall of Classic Maya Rulers, that the rulers reinforced community cohesion, as well as their own status, by adopting traditional domestic rituals and performing them on a grand scale.

Nearly everything royal emerged or developed or evolved from domestic practices. So it makes sense to turn that around and use what we know about the rulers to interpret what we find in the commoners’ homes.

Lucero has spent more than 20 years studying settlements and sacred sites that were important to the Maya in Belize, and works under the auspices of the Institute of Archaeology, which is part of the National Institute of Culture and History, Government of Belize. The study, from University of Illinois anthropology professor Lisa J Lucero, appears in the Journal of Social Archaeology.

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Natural Selection Alone can Explain Eusociality

25 August 2010, 7:00 pm

Darwinian evolution was thought to apply primarily at the individual level. Survival of the fittest implied that selfishness was essential for any organism, and so altruism could not exist. Yet, eusocial organisms, such as ants, wasps, and bees, form hierarchical social systems with reproductive queens and sterile workers. So, many insects are taking the evolutionarily counterintuitive step of sacrificing their own reproduction, and instead caring for the offspring of others. These insects, altruistically contributing to their community’s welfare, not themselves reproducing but sacrificing themselves for the greater good of the colony, are common, but should not exist!

Indeed, eusocial insects are remarkably successful. Just two percent of insects are eusocial, but they consist of over sixty percent of all insect biomass. The biomass of ants alone is more than half that of all insects, exceeding that of all terrestrial nonhuman vertebrates combined. Such selflessness in eusocial insect colonies has been explained by genetic relatedness called kin selection. It was a cornerstone of evolutionary biology, explaining social and cooperative behavior across the animal kingdom, even in humans. The trouble with kin selection is that it simply does not fit the data, according to Harvard scientists:

For the past four decades kin selection theory… has been the major theoretical attempt to explain the evolution of eusociality. Here we show the limitations of its approach.
Prof E O Wilson

When eusociality happens in insect species that have a colony of siblings, all with the same mother, the queen, they are plainly closely related, having a majority of the same genes. But eusociality in insect species in which siblings were less related to each other, and even in a mammal, the naked mole rat, showed that high genetic relatedness, “inclusive fitness”, and eusociality no longer need correlate. Wilson, the Pellegrino University Professor, Emeritus, at Harvard says:

The empirical evidence gathered in our paper demonstrates that eusociality is exceedingly rare because species must navigate a lengthy “evolutionary labyrinth” to reach this state. We hope our new theory for the evolution of eusociality will open up sociobiology to new avenues of research by liberating the study of social evolution from mandatory adherence to kin selection theory. After four decades ruling the roost, it is time to recognize this theory’s very limited prowess.

The new theory proposed by evolutionary biologist, Wilson, a founder of modern sociobiology, and mathematical biologists, Martin A Nowak and Corina E Tarnita, shows that straightforward natural selection theory alone can explain the evolution of eusocial behavior, without the need for kin selection theory.

Nowak, professor of mathematics and of biology at Harvard and director of the university’s Program for Evolutionary Dynamics says that inclusive fitness theory (IFT), which tries to calculate fitness effects conferred on relatives, sometimes may be a suitable alternative to standard population genetics, but generally is not. This analysis shows that IFT rests on assumptions which rarely hold in Nature. Contrary to many previous claims, IFT is not an extended theory of evolution and is not needed to explain eusociality. Standard natural selection theory represents a simpler and superior approach, and provides an exact framework for interpreting empirical observations. Tarnita, a junior fellow in Harvard’s Society of Fellows says:

Inclusive fitness theory is almost like a shortcut. It only applies to a small subset of all possible models. Outside of that subset, it doesn’t work.

Eusociality is rare, but important in evolutionary biology because the few species that adhere to it—including social insects and, to an extent, humans—rank among the planet’s most dominant. Humans, who are loosely eusocial, dominate land vertebrates. Tarnita explained:

Eusociality has arisen independently some 10 to 20 times in the course of evolution. Our model shows that it is difficult to get eusociality in the first place, but that it is very stable once it is established. A colony behaves like a “superorganism”, reproducing the genome of the queen and the sperm she has stored.

From this perspective, a worker ant is something like a cell—part of a larger evolutionary unit, not a unit unto itself:

Our model proves that looking at a worker ant and asking why it is altruistic is the wrong level of analysis. The important unit is the colony.

So, the researchers offered their alternative theory. A primordial, solitary ant, that lived near a food source—something like the primitive Martialis heureka—developed genetic mutations causing it to feed its offspring, rather than leaving them fend for themselves. This “progressive provisioning” is widespread in insects. From this single founder, selection moves to the level of colony. Another mutation kept offspring near the nest rather than leaving. The insects have natural instincts, even as solitary animals, to do certain things. Nowak continued:

Put two normally solitary wasps together, and if one builds a hole, the other puts an egg in it.

The other sees the egg, and feeds it. This alone is enough to start a small colony, from which eusociality could emerge from further mutations bringing specialization, reproduction restricted to queens alone, and favoring the colony’s success. Within this colony, a queen would be analogous to a human egg or sperm cell—a unit that embodies the whole. Worker self sacrifice in such a unit is no more nonsensical than that of a white blood cell.

In summary, the proposal has three distinct steps species can take to sidestep eusociality’s evolutionary cost:

  1. species must form groups within a population, as when nests or food attract individuals to discrete locations some distance apart, when parents and offspring remain together, or when migrating flocks follow leaders
  2. species must accumulate traits, arising through ordinary natural selection, that favor the switch to eusociality, as when Ceratina and Lasioglossum bees, on the cusp of eusociality, cooperate in foraging, tunneling, and guarding resources, and progressive provisioning, in which a female builds a nest, lays an egg in it, and then feeds or guards larvae until they mature. The candidate species must build a defensible nest
  3. individuals must develop genes supporting eusociality, whether by mutation or recombination. Crossing the threshold to eusociality essentially requires that a female and her offspring not disperse to start new, individual nests, but rather remain at the old nest. While eusocial genes have yet to be identified, at least two eusocial ant species are known to have genes that quell the urge to roam from the nest.

If these steps lead to a species becoming eusocial, the evolutionary costs of individuals foregoing reproduction are compensated by the reduced mortality of the queen and her larvae, which are protected by the colony. In some ant species, a queen, that alone might live for only a few months, can live for over 25 years as part of a colony, producing millions of offspring in the process.

The new theory explains everything that kin selection does, plus what it does not. The set of steps is the evolutionary “labyrinth”, the navigation of which is difficult and so rarely happens. So, eusociality is rare. But neither kin selection nor inclusive fitness need be invoked, either in eusociality, or in any cooperative behavior. Tarnita said the new theory of eusociality may help describe how single celled organisms gave rise to multicellular organisms.

Approving the idea, David Sloan Wilson, an evolutionary biologist at Binghamton University, said everything nice about human behavior—based on interactions among genetic relatives during the Stone Age, and now being incorrectly expressed—is pathetic as an explanatory framework. Especially troubling to him is that kin selection, with its intuitive appeal to our preference for family over strangers, has been applied to human social life. Tarnita comments that human selflessness and cooperation is of a different sort, involving the interaction of culture and sentience, not just genetics and environment:

There are certain things we can learn from ants, but I wouldn’t try to draw a parallel. It’s easier to think about ants, but people are complicated.

Disapproving, Rice University’s David Queller thought the new model “involves, and I suspect requires, close kinship”.

The reaction is mixed, and there will doubtless be volleys from either side to come. It seems likely, though, that the original small colony would arise from a family grouping, so the participants will be kin, even if the model could notionally work with unrelated solitary insects. The authors do not totally write off kin selection, simply considering it to apply to a “subset” of models of eusocial evolution. Maybe the subset is necessary, if not sufficient, for any species to enter the “labyrinth”!

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Why the Isle of Wight is Dinosaur Island

24 August 2010, 11:13 pm
[caption id="attachment_3216" align="aligncenter" width="500" caption="An impression of the Isle of Wight in the early Cretaceous period"]An impression of the Isle of Wight in the early Cretaceous period[/caption]

PhysOrg.com—The university of Portsmouth reports on research by one of its palaeontologists, Dr Steve Sweetman, and Dr Allan Insole of the University of Bristol. They have revealed that fires and floods raged across the Isle of Wight some 130 million years ago. The Island’s once violent weather explains why thousands of tiny dinosaur teeth and bones lie buried alongside the huge bones of their gigantic relatives, making the Isle of Wight the richest source of mixed dinosaur remains of the early Cretaceous in the world. It is Dinosaur Island!

When a fire was rapidly followed by an intense flood a snapshot of life on the Isle of Wight 130 million years ago was taken and preserved for us to see today, making the Isle of Wight one of the most important dinosaur sites in the world. Apart from the sheer diversity of dinosaurs found on the island we also have the remains of the animals and plants that lived with them.
Dr S Sweetman

During the Early Cretaceous when dinosaurs roamed, the climate was much warmer than today. This was partly to do with the geographical position of the Isle of Wight at the time—the latitude was roughly where Gibraltar is now—but also reflects the extreme greenhouse conditions of that era. Rainfall occurred all year round, but during the summer months, when temperatures soared to between 36-40oC, evaporation exceeded rainfall causing drought conditions. At these times vegetation became parched leaving it vulnerable to fires caused by lightning strikes.

Occasionally very heavy rain would follow electrical storms and wild fires causing flash floods. These swept up all loose objects in their path, swallowed complete dinosaur skeletons and eroded floodplain sediments. The more debris and sediment the water collected the thicker and thicker it became until eventually it was like mixed concrete.

This chaotic mixture, in which most of the skeletons became jumbled up, was then deposited in hollows to form what are now known as the island’s plant debris beds, so called because they contain large amounts of scorched and unburned plant fossils ranging in size from large logs to tiny fragments of leaves. The rotting plants in these beds removed oxygen providing ideal conditions for the preservation of bones.

Dr Sweetman, in summary, said:

On the Isle of Wight you get a complete muddle of the smallest fossils blended with the biggest, nothing quite like it has been seen anywhere else in the world. The plant debris beds and the mixture of fossils they contain are unique to the island.

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New Ideas about 85-million-year-old sea monster: Mosasaur

12 August 2010, 7:30 pm
[caption id="attachment_2836" align="aligncenter" width="400" caption="The Natural History Museum of Los Angeles Countys mosasaur fossil contains four slabs, which make up a virtually complete, 20-foot specimen. Pictured here is the skull portion of the specimen. Credit: Courtesy of the Dinosaur Institute, NHM"]Mosasaur fossil at Natural History Museum of LA County[/caption]

PhysOrg.com—One of the ocean’s most formidable marine predators, the marine mosasaur Platecarpus, lived in the Cretaceous Period some 85 million years ago and was thought to have swum like an eel. An international team of scientists have reconceived the animal’s morphology, or body plan, based on a specimen at the Natural History Museum of Los Angeles County.

The mosasaur specimen was discovered in Kansas in 1969, and acquired by the NHM. It contains four slabs, which make up almost a complete, 20 foot specimen. Dr Chiappe, curator of the 15,000-square foot landmark exhibition that opens at the museum in 2011, explained:

It is one of several exceptional fossils that will be featured in Dinosaur Mysteries.
[caption id="attachment_2837" align="aligncenter" width="400" caption="One of the oceans most formidable marine predators, the mosasaur "]Reconstruction of a living Mosasaur[/caption]

In the meantime, the fossil will be temporarily on display at the museum’s Dino Lab, a working lab located on the second floor of the museum, where paleontologists prepare fossils in full view of the public.

The specimen is the finest preserved mosasaur in existence, according to Dr Johan Lindgren, lead author of the published study. It retains traces of a partial body outline, putative skin color markings, external scales, a down turned tail, branching bronchial tubes, and stomach contents (fish). Using it, the scientists demonstrate that a streamlined body plan and crescent shaped tail fin were already well established in Platecarpus, and that these key features evolved early in the evolution of mosasaurs. Noting the highly specialized tail fin, the new study assert that mosasaurs were better swimmers than previously thought and that they swam more like sharks than eels. The findings underscore how these adaptations for fully aquatic existence evolved rapidly and convergently in several groups of Mesozoic marine reptiles, as well as in extant whales. Dr Chiappe said:

This fossil shows evolution in action, how a successful design was developed time after time by different groups of organisms adapting to life in similar environments. It highlights once again the potential for new discoveries to challenge well-established interpretations about dinosaurs and other animals that lived with them.

Dr Kevin Padian, a paleontologist at the University of California, Berkeley, commenting on the new assessment, said:

From this beautifully preserved specimen it seems that advanced, shark like swimming began in mosasaurs millions of years earlier than we previously thought. This study is the best possible proof that active research by curators and staff is the most essential component of a museum dedicated to educating the public.
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Menopause

11 August 2010, 7:00 pm

One feature of human beings appears to be unique. It is the menopause. Humans are the only animal in which female fertility shuts down while they are still capable of having children. Most women stop producing eggs between 40 and 50, while they are still in the prime of life. Why? One theory is that it is a mistake. Women, through the stresses of civilisation have started to do this in error. The answer is hormone replacement therapy, which allows them to continue as before.

An alternative idea is that the menopause is an evolutionary adaptation that confers survival benefits on to the species. Alan Rogers of the University of Utah, has developed mathematical models which confirm the usefulness of the strategy. The idea is essentially that there is more advantage in a middle aged woman not having more children of her own but helping her own children and their children. Once a new child is going to take more than three years requiring mother’s attention, then the advantage of having grandma comes clearly into the equation. Furthermore, when it is considered that the grandma’s children, if she continued to have them, were increasingly likely to be left motherless before they reached adulthood, the selective pressure is still higher.

The reason for the evolution of human menopause is because human children need long and costly parental attention to bring them to maturity and so older women cannot continue to have children which she might not be able to see through to maturity but instead helps the survival of her own line by supporting her daughters.

Contrary to this Mormon idea, however, is the evidence of primitive societies that post menopausal women, far from taking on a granny role, become important figures in their societies. These women seem not to have the hot flushes and other menopausal symptoms of western women. One reason for this might be their higher levels of prolactin and oxymycin from breast feeding continually. Such women certainly do not have the negative feelings of lost youth felt by western women and display it often in a gusto for sex without concern. Menopause is therefore truly the natural contraceptive which evolved to let the labourers have some fun later in life!

Originally posted 2009-06-04 23:56:58. Republished by Blog Post Promoter

Filed under Anthroposaurus sapiens, Dinosaurs, Homo, News. Tagged , , , ,
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