Largest New Nephila Spider Discovery In 130 Years

A giant golden orb-web exceeding 1 meter in diameter, spun by a Nephila inaurata spider. Image Credit: Matjaz Kuntner

Largest New Nephila Spider Discovery In 130 Years

Scientists, Jonathan Coddington of the Smithsonian’s National Museum of Natural History and Matjaz Kuntner of the Slovenian Academy of Sciences and Arts, have found the world’s largest species of golden orb-weaver spider in the tropics of Africa and Madagascar. The discovery marks the first identification of a new Nephila spider since 1879.

Codding stated in a press release, “We fear the species might be endangered, as its only definite habitat is a sand forest in Tembe Elephant Park in KwaZulu-Natal. Our data suggest that the species is not abundant, its range is restricted, and all known localities lie within two endangered biodiversity hotspots: Maputaland and Madagascar.”

Tiny male Nephila spiders are dwarfed by their female counterparts. Image Credit: Matjaz Kuntner and Jonathan Coddington/PLoS ONE

This excerpted and edited from Wired Science -

Even-More-Gigantic Giant Orb Spider Discovered
By Hadley Leggett, Wired Science - October 20, 2009, 8:00 pm

Females of the new species, Nephila komaci, measure a whopping 4 to 5 inches in diameter, while the male spiders stay petite at less than a quarter of their mate’s size. So far, only a handful of these enormous arachnids have been found in the world.
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The first potential specimen of the new species was uncovered by Coddington and his colleague Matjaz Kuntner in 2000. They found a huge female orb-weaver among a museum collection of spiders in Pretoria, South Africa, and she didn’t match the description of any known spider. Although they hoped the unusual-looking giant represented a new species, several dedicated expeditions to South Africa failed to find any live spiders of a similar description.

Then, in 2003, a second specimen from Madagascar was found at a museum in Austria, suggesting that the first spider hadn’t been a fluke. But despite a comprehensive search through more than 2,500 samples from 37 museums, no additional specimens turned up.
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Finally, three live spiders have been found to prove the scientists wrong: A South African researcher found two giant females and one male in Tembe Elephant Park, proving that the new species was not extinct, just incredibly rare.

“Only three have been found in the past decade,” Kuntner wrote in an e-mail to Wired.com. “None by our team, despite focused searches. Only an additional two exist in old museum collections. Compared to thousands of exemplars of other Nephila species in museums, that is disproportionately rare.”
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Like all Nephila spiders, females of the new species spin huge webs of golden silk, often more than 3 feet in diameter. In the report of the discovery of this rare spider, published Tuesday in PLoS One, the researchers also addressed the evolution of the dramatic size difference between male and female orb-weavers.
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The Eye(s) Have It! – A Genetic Switch

Eyes are organs of vision that detect light. Different kinds of light-sensitive organs are found in a variety of organisms. The simplest eyes do nothing but detect whether the surroundings are light or dark, while more complex eyes can distinguish shapes and colors. -- Scientists believe they could grow eyeballs from stem cells in the lab, the process would be a boon to individuals with damage to cells within the eye, including retinal disorders. Image Credit: Wikipedia

The Eye(s) Have It! – A Genetic Switch

An enzyme that researchers have isolated leads to replacement therapy procedures for the eye and replacement parts for the eye.

In a new study released through the journal, Nature, a nitrogen-bearing molecule is the key to setting off a series of steps that result in eye formation in frogs.

The researchers think the same mechanism for triggering eye development can apply across a wide range of species, including human beings. It is interesting to note, mutations to the human equivalent of this enzyme lead to severe head and eye defects in humans.

When researchers injected a specific enzyme into frog embryos, the resulting tadpoles showed an extra eye (right image). The left image shows normal tadpole eye development. Image Credit: Masse, K., Bhamra, S., Eason, R., Dale, N. and Jones, E./Nature

This excerpted from LifeScience -

Scientists Envision Growing Human Eyeballs
By Jeanna Bryner, LiveScience Staff Writer -- posted: 24 October 2007

A genetic switch that gives tadpoles three eyes could allow stem-cell scientists to eventually grow human eyeballs or at least create replacement parts needed for repair jobs.

If scientists could grow eyeballs from stem cells in the lab, the process would be a boon to individuals with damage to cells within the eye, including retinal disorders.

"If you knew all the genes, and how to turn them on, that you needed to make an eye, you could start with very early embryonic cells and turn on all the right genes and grow an eye in a dish," said co-leader of the study Nicholas Dale, a neuroscientist at the University of Warwick in England.

"What I think is the more realistic possibility is to make precursor cells for different bits of the eye, which could then be transplanted and differentiate in-situ to replace damage to the retina or the lens or iris," Dale told LiveScience.

Scientists already had established the amphibian genes that initiate and direct eye development, which they refer to as Eye Field Transcription Factors (EFTFs). How these genes get activated in the right location at a certain time during development had been cloaked in mystery.
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Dale and University of Warwick developmental biologist Elizabeth Jones, along with colleagues, discovered the eye-switch while investigating how "ectoenzyme" molecules located on the external surface of cells contributed to the development of locomotion in the African clawed frog (Xenopus laevis). The biologists injected the molecules into frog embryos that comprised just eight cells.

One of the ectoenzymes triggered wonky eye development. When added to cells that would eventually form the head, the resulting tadpole sported three eyes instead of two. An even stranger sight resulted when they injected the ectoenzyme into other developing body cells. The molecule caused an additional "ectopic" eye, leading to tadpoles with a spare peeper growing out of the side, abdomen or even along the tail.

On a molecular level, the scientists say the enzyme converts a burst of the energy-carrying molecule ATP into ADP, which ultimately turns on the embryo's eye-making machinery.

The researchers think the same mechanism for triggering eye development applies across a wide range of species, including us. Mutations to the human equivalent of this enzyme lead to severe head and eye defects in humans.
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Two Mouths To Feed And Only One Way To Breathe - Gills

A very common type of moray eel in the Philippines, this variety of moray is usually small in size compared to many others. This specimen is typical-- about 2 feet long. Image Credit: Divegallery

Two Mouths To Feed And Only One Way To Breathe - Gills

Ever wonder how Hollywood comes up with the ideas they come up with to scare us and creep us out? Well, how about right here in the oceans on the Oblate Spheroid.

It has been recently discovered that the Moray Eel uses an eating method that employs two sets of clamping jaw mechanisms – like right out of Hollywood and the movie “Aliens”

This from San Jose Mercury News -

The creepy truth about moray eels
By Betsy Mason - STAFF WRITER - Article Launched: 09/05/2007 09:51:00 AM PDT

It's like a scene from an Aliens movie: a scaly underwater creature looking something like a piranha crossed with a python strikes at its prey which is then reeled deeper into the beast's throat by a second set of toothy jaws.

But this sinister animal isn't a figment of a Hollywood director's imagination, suddenly bursting out of a character's stomach, terrifying audiences. It's a real-life product of evolution.

As if eels weren't already creepy enough, scientists at UC Davis have discovered that some eels have an extra set of jaws deep in their throats that launch forward into their mouths to help pull prey in.

"It looks like a funny pair of forceps with curved sharp teeth," said evolutionary biologist Rita Mehta, lead author of the research, which appears Thursday in Nature.

Mehta and functional morphologist Peter Wainwright captured the odd feeding behavior using high-speed video recordings of eels in lab tanks. Slowed down, the video reveals the jaws coming forward into the mouth and taking hold of a piece of food.

"It was one of those gee-whiz moments when we were absolutely ecstatic," Mehta said. "It was just astounding."

Before the discovery, scientists thought that all aquatic predators swallowed their prey using suction. By dropping the lower jaw and creating a flow of water into their mouths, they draw in the prey. The two species of moray eels studied by Mehta and Wainwright are the first examples of an alternative feeding method.

Other bony fish also catch their prey with their teeth, but they still use suction to swallow it.

Snakes accomplish the same thing by alternately ratcheting the left and right sides of their jaws along their quarry.

Mehta thinks the eels' extra jaws may have evolved to help the eels catch animals in small cracks and crevices in the coral they inhabit. While suction requires expansion of the mouth, the eel's double-jaw trick allows it to remain long and skinny, and may have helped them earn their place as top predator on the coral reef.

The discovery shows that suction feeding in not the final word on fish feeding behavior.

"There are probably more alternatives to suction feeding," Mehta said. "This is probably the tip of the iceberg.

"We're just starting to look."
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Toothy Find In Ethiopia Changes Evolutionary Assumption

Digital Renderings Of Gorilla Right Upper Molors - This undated file photo shows Chororapithecus abyssinicus teeth and a female gorilla tooth row. Ten-million year old fossils discovered in Ethiopia, the earliest direct ancestors of modern gorillas ever found, shows that humans and apes probably split six or seven millions years earlier than widely thought, according to landmark study released Wednesday. Image Credit: AFP via PHYSORG

Toothy Find In Ethiopia Changes Evolutionary Assumption

The scientific community, through unearthed fossil evidence, has always assumed that humans evolved from apes. A new fossil may push back the approximate beginning of this split by millions of years.

What actually becomes the most significant piece of information gleaned from this uncovered evidence is that the handful of teeth from the earliest direct ancestors of modern gorillas leave virtually no doubt that both humans and modern apes did indeed originate from Africa. This is the conclusion found in the study that accompanied the find published in “NATURE”.

The scientists leading the team that found the fossils -- Gen Suwa of the University of Tokyo, and Ethiopian paleontologists Berhane Asfaw and Yonas Beyene -- calculated that the human-orangutan split "could easily have been as old as 20 million years." The teeth fragments, found in barren scrubland some 170 kilometres (100 miles) east of Ethiopia's capital Addis Ababa, almost went unnoticed. Asfaw recalled the chance discovery. "It was our last day of field survey in February 2006, and our sharp-eyed field assistant, Kampiro, found the first ape tooth, a canine," he said. "He picked it up and showed it to me, and I knew that this was something new -- Ethiopia's first fossil great ape." Image Credit: AFP

This from AFP via PHYSORG.com -

Fossil find pushes human-ape split back millions of years
AFP - Aug 24 08:17 AM US/Eastern

Ten million-year-old fossils discovered in Ethiopia show that humans and apes probably split six or seven million years earlier than widely thought, according to landmark study released Wednesday.
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The near total absence to date of traces on the continent of apes from this period had led many scientists to conclude that the shared line from which humans and living great apes emerged had taken a long evolutionary detour through Eurasia.

But the study, published in the British journal Nature, "conclusively demonstrates that the Last Common Ancestor (of both man and ape) was strictly an African phenomenon," commented paleoanthropologist Owen Lovejoy of Kent State University in Ohio.

Lovejoy described the fossils as "a critically important discovery," a view echoed by several other scientists who had read the paper or seen the artifacts.

"This is a major breakthrough in our understanding of the origin of humanity," Yohannes Haile-Selassie, a physical anthropologist at the Cleveland Museum of Natural History, told AFP.

The most startling implication of the find, the scientists agree, is that our human progenitors diverged from today's great apes -- including gorillas, orangutans and chimpanzees -- several million years earlier than widely accepted research based on molecular genetics had previously asserted.
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"We know nothing about how the human line actually emerged from apes," the authors of the paper noted.

But the new fossils, dubbed "Chororapithecus abyssinicus" by the team of Japanese and Ethiopian paleoanthropologists who found them, place the early ancestors of the modern day gorilla 10 to 10.5 million years in the past, suggesting that the human-ape split occurred before that.

There is broad agreement that chimpanzees were the last of the great apes to split from the evolutionary line leading to man, after gorillas and, even earlier, orangutans.

Conventional scientific wisdom, based on genetic "distances" measured by molecular geneticists, had placed the divergence between chimps and humans some five to six million years ago. Orangutans are thought to have parted company with our ancestors 13 to 14 million years ago.

"If the new discovery is in the gorilla lineage, then this will definitely substantially push back the split time between apes and humans," Halie-Selassie at Kent State told AFP.
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They determined that the teeth belonged to gorilla ancestors based on unique shared characteristics of the molars, which had evolved for a diet of fibrous foods such as stems and leaves.

The match is not exact, however, and could prompt some scientists to challenge the findings.
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