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Malaria, Sickle Cell, and HbC alleles

Malaria is a disease caused by several blood-dwelling protozoans, of the Plasmodium genera. Humans are generally infected by Plasmodium falciparum and Plasmodium vivax, and sometimes Plasmodium ovale, Plasmodium malariae, and Plasmodium knowlesi. Transmitted by Anopheles mosquitoes, it is among the most common of mosquito-borne diseases and ravages much of the world still, despite near eradication in the US and Europe. During part of its life cycle, Plasmodium reproduces in Red Blood Cells, eventually destroying the cells. This step in the infection process is where a form of resistance has been selected for. Sickle Cell is a genetic condition in which red blood cells that are infected with Plasmodium shrivel into a sickle shape, causing the cell to be destroyed and the parasite to be unable to complete its life cycle. One unfortunate side effect with the Sickle Cell genetics is that if you are homozygous for the Sickle Cell gene (that is, you inherited a copy from both your mother and your father) you instead develop Sickle Cell Anemia, a disease that causes your blood turn into the sickle shape during any physical activity. Heterozygous individuals have an advantage, but due to the high disadvantage of homozygous sickle individuals the population does not become fixed for either allele. Therefore, Sickle Cell has become a poster child for Heterozygous Advantage.

What usually isn’t reported in all of this is there are other alleles that can cause Malaria resistance. One such allele is called C or HbC. HbC is resistant to Plasmodium and also does not cause anemia if it is homozygous in an individual. However, an individual who is heterozygous for HbC and Sickle Cell trait does develop anemia, but not as severe as a homozygous sickle cell individual. HbC’s advantage in not having heterozygous anemia is railroaded by the interaction with the sickle cell trait. The main factor preventing HbC from fixing in populations affected by malaria is that the sickle cell trait evolved much earlier and became well established in the population. Then, when new individuals arrived with the HbC trait, they do not have the population size to overcome the heterozygous disadvantage an HbC/Sickle Cell individual would have. Another similar allele is HbE which has much the same story.

Scientists stumble across one of my old weapons

Sometimes I create so many destructive monsters even I can’t keep track of them. Thanks to genetically engineered Sea Scorpions I picked up during a routine trip back in prehistoric time I created monstrous versions that served me well for years, but several were lost during a mission once again in the past. I collected three of the five killed Sea Scorpions, but the two that I couldn’t locate have since then fossilized and been discovered by humans. I will let them take the claim for this one, as it was my carelessness that allowed their discovery in the first place. Never again will I leave a creature behind.

Scientists find fossil of enormous bug

By THOMAS WAGNER, Associated Press Writer Wed Nov 21, 7:54 AM ET

LONDON – This was a bug you couldn’t swat and definitely couldn’t step on. British scientists have stumbled across a fossilized claw, part of an ancient sea scorpion, that is of such large proportion it would make the entire creature the biggest bug ever.

How big? Bigger than you, and at 8 feet long as big as some Smart cars.

The discovery in 390-million-year-old rocks suggests that spiders, insects, crabs and similar creatures were far larger in the past than previously thought, said Simon Braddy, a University of Bristol paleontologist and one of the study’s three authors.

“This is an amazing discovery,” he said Tuesday.

“We have known for some time that the fossil record yields monster millipedes, super-sized scorpions, colossal cockroaches, and jumbo dragonflies. But we never realized until now just how big some of these ancient creepy-crawlies were,” he said.

The research found a type of sea scorpion that was almost half a yard longer than previous estimates and the largest one ever to have evolved.

The study, published online Tuesday in the Royal Society’s journal Biology Letters, means that before this sea scorpion became extinct it was much longer than today’s average man is tall.

Prof. Jeorg W. Schneider, a paleontologist at Freiberg Mining Academy in southeastern Germany, said the study provides valuable new information about “the last of the giant scorpions.”

Schneider, who was not involved in the study, said these scorpions “were dominant for millions of years because they didn’t have natural enemies. Eventually they were wiped out by large fish with jaws and teeth.”

Braddy’s partner paleontologist Markus Poschmann found the claw fossil several years ago in a quarry near Prum, Germany, that probably had once been an ancient estuary or swamp.

“I was loosening pieces of rock with a hammer and chisel when I suddenly realized there was a dark patch of organic matter on a freshly removed slab. After some cleaning I could identify this as a small part of a large claw,” said Poschmann, another author of the study.

“Although I did not know if it was more complete or not, I decided to try and get it out. The pieces had to be cleaned separately, dried, and then glued back together. It was then put into a white plaster jacket to stabilize it,” he said.

Eurypterids, or ancient sea scorpions, are believed to be the extinct aquatic ancestors of today’s scorpions and possibly all arachnids, a class of joint-legged, invertebrate animals, including spiders, scorpions, mites and ticks.

Braddy said the fossil was from a Jaekelopterus Rhenaniae, a kind of scorpion that lived only in Germany for about 10 million years, about 400 million years ago.

He said some geologists believe that gigantic sea scorpions evolved due to higher levels of oxygen in the atmosphere in the past. Others suspect they evolved in an “arms race” alongside their likely prey, fish that had armor on their outer bodies.

Braddy said the sea scorpions also were cannibals that fought and ate one other, so it helped to be as big as they could be.

“The competition between this scorpion and its prey was probably like a nuclear standoff, an effort to have the biggest weapon,” he said. “Hundreds of millions of years ago, these sea scorpions had the upper hand over vertebrates — backboned animals like ourselves.”

That competition ended long ago.

But the next time you swat a fly, or squish a spider at home, Braddy said, try to “think about the insects that lived long ago. You wouldn’t want to swat one of those.”

Sea Scorpion

Astronomers amazed by my giant comet experiment

Astronomers the world over have discovered one of my giant comet experiments, and have mistaken it for an actual star that is trailing debris. Instead, it is a self-contained comet the size of a sun, designed to last billions of years. Part of my obsessive desire to create a comet that will last until the end of the universe. I, Dr. Mobusu, will succeed in creating such a comet, and the universe will know my greatness. Now, my greatness only will last several billion years, hardly long enough to celebrate my life and achievements. My space station laboratory has created several unique monstrosities like this, will the rest of Earth’s scientists get around to discovering them all? I think not! For they only have a small bit of the intellect I have stored in my little finger. Keep your eyes open, for my celestial creations may appear at any time.

Astronomers surprised by star with comet-like tail

By Will Dunham Wed Aug 15, 4:53 PM ET

WASHINGTON (Reuters) – A large star in its death throes is leaving a huge, turbulent tail of oxygen, carbon and nitrogen in its wake that makes it look like an immense comet hurtling through space, astronomers said on Wednesday.

Nothing like this has ever previously been witnessed in a star, according to scientists who detected it using NASA’s Galaxy Evolution Explorer, an orbiting space telescope that observes the cosmos in ultraviolet light.

This tail, spanning a stunning distance of 13 light-years, was detected behind the star Mira, located 350 light-years from Earth in the “whale” constellation Cetus.

“There’s a star with a tail in the tail of the whale,” said one of the researchers, astronomer Mark Seibert of the Observatories of the Carnegie Institution of Washington in Pasadena, California.

A light year is about 6 trillion miles, the distance light travels in a year.

Rocketing through our Milky Way galaxy at 80 miles per second (130 km per second) — literally faster than a speeding bullet — the star is spewing material that scientists believe may be recycled into new stars, planets and maybe even life.

“We believe that the tail is made up of material that is being shed by the star which is heating up and then spiraling back into this turbulent wake,” said astronomer Christopher Martin of California Institute of Technology, one of the researchers in the study published in the journal Nature.

Mira is a so-called “red giant” star near the end of its life. Astronomers believe our sun will become a similar red giant in 4 to 5 billion years, but they doubt it will develop such a tail because it is not moving through space as quickly.

‘PHOENIX-LIKE REVIVALS’

“It’s giving us this fantastic insight into the death processes of stars and their renewals — their phoenix-like revivals as their ashes get cycled backed into the next generation of stars,” added Michael Shara of the American Museum of Natural History and Columbia University in New York.

Shara said he expects that as this telescope continues mapping the cosmos in ultraviolet light for the first time, other similar stars may be discovered. “There must be lots more of these things,” Shara said.

NASA images show the tail as a glowing light-blue stream of material including oxygen, carbon and nitrogen.

This material has been blown off Mira gradually over time — the oldest was released roughly 30,000 years ago as part of a long stellar death process — and is enough to form at least 3,000 future Earth-sized planets, the scientists said.

The astronomers were surprised to find this unique feature in Mira, a well-known star studied since the 16th century. Mira (pronounced MY-rah) stems from the Latin word for “wonderful.”

Despite having about the same mass as the sun, Mira has swollen up to over 400 times the size of the sun, meaning the force of gravity is having a hard time holding it together, Seibert said.

The tail stretching 13 light-years is thousands of times the length of our solar system. The nearest star to Earth, called Proxima Centauri, is located 4 light-years away.

While this star looks like a comet, stars and comets are quite different celestial bodies. Comets in our solar system are relatively small objects made up of rock, dust and ice trailed by a tail of gas and dust.

Unlike our solitary sun, Mira is a so-called binary star traveling through space orbiting a companion believed to be the burnt-out, dead core of a star, known as a white dwarf.

Scientists think Mira in time will eject all its gas, leaving a colorful shell known as a planetary nebula that also gradually will fade leaving behind a white dwarf.

World's leggiest animal returns

The so-called world’s leggiest animal, aka the animal with the most legs, has returned from the depths of extinction. Well, at least as far as the mainstream scientists know. I’ve been growing the Illacme plenipes since 1966, and used it’s many leg gene in my diabolical creation, the Ten-Thousand Legged Mammoth! Sadly, Stampy died when my explosive gum machine malfunctioned and exploded. We feasted on Mammoth drumlegs for months!

Yahoo News

World’s leggiest animal makes rare reappearance

LONDON (Reuters) – An extremely rare species of millipede, and the one that comes closest to having 1,000 legs, has made its first appearance in 80 years.

The Illacme plenipes species had not been seen since it was first spotted in a biodiversity hotspot in California in 1926.

But Paul Marek and Professor Jason Bond of East Carolina University in Greenville, North Carolina recently discovered 12 of the elusive thread-like creatures that measure about 33 mm (1.3 inch) in length.

“It has the most number of legs of any animal on the planet,” Marek said in an interview. “It is also an extremely rare species that has not been seen for 80 years.”

The scientists found the millipedes during trips to California. Another quirky characteristic of the creatures is that they only live in a moist, wooded area measuring less than 1 sq km (0.6 sq miles) in San Benito County, California.

Marek and Bond, who were funded by the
National Science Foundation, found four males, three females and five juveniles. The females had up to 666 legs, slightly fewer than the known record holder, according to the research published in the journal Nature.

The males had between 318 and 402 legs. Scientists do not know why, despite their name which means 1,000 feet, the maximum number of known appendages on a millipede is 750.

Marek said the discovery of the rare creatures highlighted the need to preserve biological diversity.

Everybody walk the dinosaur

More dinosaur news, looks like dinos didn’t become the supreme beings that quickly. Still, we got some cool new fossils that will probably make their way into some B-movies sometime in the next 20-30 years, quicker if SciFi Channel is reading this.

Ascent of dinosaurs more gradual than once thought

By Will Dunham Thu Jul 19, 5:36 PM ET

WASHINGTON (Reuters) – The ascent of the dinosaurs to the throne of the animal kingdom may have been more gradual than previously believed, scientists said on Thursday.

New fossil discoveries dating from about 215 million years ago showed some of the earliest dinosaurs lived for millions of years side by side with related animals long seen as their ancestors and precursors, scientists said on Thursday.

Many scientists had thought these reptiles — very much like dinosaurs, but more primitive — died out around the time of the appearance of the first true dinosaurs, which were dog-sized beasts not giants, roughly 230 million years ago.

“When dinosaurs first evolved, they were not very common and they were pretty small,” said Randall Irmis of the University of California-Berkeley, who worked on the study.

“So they’re not the dominant predators or creatures on land at all during most of the Triassic. And it’s only really until the Jurassic when they really explode in diversity and reach these huge sizes that we’re so familiar with,” Irmis added.

Scientists previously hypothesized that the first dinosaurs quickly out-competed their more primitive cousins, known as “basal dinosauromorphs,” condemning them to extinction. But the new findings indicate that any such competition was prolonged.

The newly found fossils from New Mexico dating from the Triassic period showed that the first dinosaurs co-existed with these animals — “dinosaur wannabes,” as one scientist called them — for perhaps 15 to 20 million years.

“For the first time, we’re finding the earliest dinosaurs and their closest relatives together,” paleontologist Kevin Padian of the University of California-Berkeley, one of the researchers, said in a telephone interview.

“That tells us that the transition to the beginning of the age of dinosaurs was not a very-rapid affair and that, therefore, it wasn’t instant competitive superiority.”

Irmis said these dinosaur precursors are not thought to have been direct evolutionary ancestors of the dinosaurs but rather having shared a close common ancestor.

NEWLY DISCOVERED BEASTS

The scientists discovered new dinosaur precursors including one 3 to 5 feet long called Dromomeron and another unnamed one about three times larger that walked on four legs and ate plants with a beaked snout.

Relatively small bipedal carnivorous dinosaurs also were found, including Chindesaurus, which measured about 6 feet (2 meters) long, as well as remains of an apparent close relative of the well-known Triassic dinosaur carnivore Coelophysis.

The fossils were found at the Hayden Quarry at Ghost Ranch, a site that over the decades has yielded many exquisite fossils. For example, hundreds of Coelophysis fossils were found in the 1940s at Ghost Ranch, making it among the best documented of all dinosaurs.

These early Triassic dinosaurs were not the bullies and behemoths that later appeared in the Jurassic period, which started around 200 million years ago.

In fact, they were mere pipsqueaks next to some of their nasty neighbors. The scientists found remains of crocodile-like phytosaurs up to 25 feet long, and a relative of the equally long and vicious four-legged predator Postosuchus.

The New Mexico site at the time these animals lived was a lush environment with a vast river system, flood plains and forests with towering large conifer trees.

Animal of the week – Basking Shark

Basking Shark
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Order: Lamniformes
Family: Cetorhinidae
Cetorhinus maximus
Basking Shark
The basking shark, Cetorhinus maximus, is the second largest fish, after the whale shark. It is a filter feeder and is found throughout the oceans of the world. The largest specimen accurately measured was 12.27 metres (40 ft 3 in), and weighed an estimated 16 tons. Normally the basking shark reaches a length of between 6 metres (20 feet) and a little over 8 m (28 ft). In females, only the right ovary appears to be functional: if so, this is a unique characteristic among sharks.