Volcano Eruption in Galapagos National Park

La Cumbre volcano in the Galapagos Islands started spewing lava, gas and smoke on the Fernandina Island. The most recent volcanic activity on Fernandina Island occurred in May 2005. I was fortunate to attend a course that focused on the biology and evolution of the Galapagos last summer - I never stepped foot on Fernandina because my group explored the eastern portion of the archipelago.

It still breaks my heart that this eruption may have a detrimental effect on the wildlife endemic to the island. The following excerpt was taken from the Glob Gazette News Blog.

In a statement it said the eruption is not a threat to people living on nearby Isabela Island. But it added that lava flowing to the sea will likely affect marine and terrestrial iguanas, wolves and other fauna.

The iguanas we encountered on the islands were unlike any reptile I've ever seen. They also were oblivious to our presence - or mildly annoyed at worst.

This picture (left) features the Galapagos marine iguana. One of their interesting and diagnostic features was the little white cap that each wore atop their heads. Due to the high salt content in their diets, they have evolved a mechanism to maintain an internal osmotic equilibrium. They sneeze to expel excess salt from salt glands that are located above the eye. This in combination with the wind results in an accumulation of white salt on their head. When I was in the Galapagos, an ongoing pursuit among group members was to photograph a marine iguana mid- sneeze, as they expelled excess salt every few minutes. Sadly, no one was successful. I will say that there is nothing cuter than a sneezing iguana.

The majority of land iguanas we saw were on Santa Fe Island. They were visible because the island had low-growing vegetation that surrounded a sparsely distrubuted Opuntia cactus forest. 

The land iguanas were quite visible, startlingly large, and usually munching on yellow purslane flowers (Protulaca lutea).

I hope the population of critters who were affected by the recent eruption are able to quickly rebound. I don't know the impact's severity at this point, but I can't say enough about the importance of conserving the Galapagos Archipelago. It represents a thriving pristine wilderness as untamed territories elsewhere - everywhere - are increasingly being forced to share resources with fatal human co-inhabitants. 

David Attenborough: Evolution from Sea to Land

The Fish-Tetrapod Transition

With the vertebrate comparative anatomy lab quickly approaching in my Animal Diversity class, I was excited to fall upon a paper that appears well-tailored to the content of my own teaching schedule (for once! geesh). This is spankin' new, published March 17, 2009, from the journal Evolution: Education and Outreach.

This paper is paricularly interesting because it outlines both the history of tetrapod evolution and the history of human's perception of the animal transition from aquatic to terrestrial habitats. It highlights the helpful fossils unearthed that helps us trace this vertebrate history, such as Icthyostega spp., and those fossils, such as the Eryops cephalus, that hindered the pursuit. In the case of the latter organism (pictured below), despite its anatomy being characteristic of an early trasitional tetrapod, its ancestral origin was found to exist much later in tetrapod evolution.

This paper also describes the reason for the recent fame of the Tiktaalik transitional fossil, as it is known from several nearly complete specimens. Its excellent preservation and diagnostic transitional tetrapod features have made it an important tool for understanding the origin of the phylogenetic tree of Tetrapoda.

"In a nutshell, the 'fish–tetrapod transition' usually refers to the origin, from their fishy ancestors, of creatures with four legs bearing digits (fingers and toes), and with joints that permit the animals to walk on land. This event took place between about 385 and 360 million years ago toward the end of the period of time known as the Devonian. The Devonian is often referred to as the 'Age of Fishes,' as fish form the bulk of the vertebrate fossil record for this time."

This paper is a great read for eager young biologists like myself searching for readable scientific papers on phylogenetics and evolution. I recommend it!

The Fish–Tetrapod Transition: New Fossils and Interpretations

Pepto-Bismol-Pink Dolphin in Louisiana

This is a peculiar find. (Thanks to Dr. Melissa Palmer for the tip)

The pink color and reddish eyes indicate albinism, an inherited condition that results in individuals lacking normal pigmentation. This special aquatic mammal drew quite a crowd when it first surfaced in Lake Calcasieu, an inland saltwater estuary north of the Gulf of Mexico in Louisiana.

The dolphin was first identified by charter boat captain Erik Rue, who said it was swimming with a pod of four other dolphins. I hope this special critter makes it despite its strange coloration.




Is this first pink dolphin observed in nature?

Actually, there are pink dolphins that reside in South America in the Amazon. The boto is the largest of the river dolphins. They have different color patterns, varying from bright pink to deep grey, depending upon their age and the geographical area where they are found. In the Arauca River in Colombia, dolphins are very pink (pictured below) and very active at the surface. They tend to become more "pink" with age because their skin becomes more translucent and the blood circulating beneath their skin becomes visible. These Amazon River Botos are close relatives to the dolphins with which we are familiar from the states. However, there are a few significant morphological differences.

In addition to the higher frequency of pink coloration among populations, the Amazon River Botos have specialized teeth that are used to crush fish and heavily armored benthic organisms such as crustaceans. They also have a big hump on their head and a ridge on their back in place of a defined dorsal fin.

da Silva V (1994) Aspects of the biology of the Amazonian dolphins Genus Inia and Sotalia fluviatilis. PhD Dissertation, University of Cambridge, Cambridge, 327 pp.

Science Fare

A student introduced me to this fine tribute to science. Bad Astromony guy, you inspire!

In April, I was asked to give a short speech to a group of local students who participated in a science fair. I wasn’t sure what to say to them, until I saw a newscast the night before the fair. The story was some typically inaccurate fluff piece giving antiscience boneheads “equal time” with science, as if any ridiculous theory should have equal time against the truth.

I sat down with a pad of paper and a pencil and scribbled down this speech. I gave it almost exactly as I wrote it.

I know a place where the Sun never sets.

It’s a mountain, and it’s on the Moon. It sticks up so high that even as the Moon spins, it’s in perpetual daylight. Radiation from the Sun pours down on there day and night, 24 hours a day — well, the Moon’s day is actually about 4 weeks long, so the sunlight pours down there 708 hours a day.

I know a place where the Sun never shines. It’s at the bottom of the ocean. A crack in the crust there exudes nasty chemicals and heats the water to the boiling point. This would kill a human instantly, but there are creatures there, bacteria, that thrive. They eat the sulfur from the vent, and excrete sulfuric acid.

I know a place where the temperature is 15 million degrees, and the pressure would crush you to a microscopic dot. That place is the core of the Sun.

I know a place where the magnetic fields would rip you apart, atom by atom: the surface of a neutron star, a magnetar.

I know a place where life began billions of years ago. That place is here, the Earth.

I know these places because I’m a scientist.

Science is a way of finding things out. It’s a way of testing what’s real. It’s what Richard Feynman called "A way of not fooling ourselves."

No astrologer ever predicted the existence of Uranus, Neptune, or Pluto. No modern astrologer had a clue about Sedna, a ball of ice half the size of Pluto that orbits even farther out. No astrologer predicted the more than 150 planets now known to orbit other suns. But scientists did.

No psychic, despite their claims, has ever helped the police solve a crime. But forensic scientists have, all the time.

It wasn’t someone who practices homeopathy who found a cure for smallpox, or polio. Scientists did, medical scientists.

No creationist ever cracked the genetic code. Chemists did. Molecular
biologists did. They used physics. They used math. They used chemistry, biology, astronomy, engineering. They used science.

These are all the things you discovered doing your projects. All the things that brought you here today.

Computers? Cell phones? Rockets to Saturn, probes to the ocean floor, PSP, gamecubes, gameboys, X-boxes? All by scientists.

Those places I talked about before? You can get to know them too. You can experience the wonder of seeing them for the first time, the thrill of discovery, the incredible, visceral feeling of doing something no one has ever done before, seen things no one has seen before, know something no one else has ever known.

No crystal balls, no tarot cards, no horoscopes. Just you, your brain, and your ability to think.

Welcome to science. You’re gonna like it here.

Parasitizing caterpillar tricks ants into service

A kind of European caterpillar can garner royal treatment from ants by mimicking the ch-ch-ch-ch of their queen, says an international research team.

Ants of the species Myrmica schencki can be fooled into carrying certain caterpillars into the colony nurseries where the fakers enjoy full care and five-star dining, explains Jeremy Thomas of the University of Oxford in England. An interloper caterpillar gains most of its body mass while luxuriating in ant care, and then turns into a Maculinea rebeli butterfly.

Chemical camouflage alone will let the caterpillars game their way into the ant colony. Now experiments show that the noises the caterpillars make get them the premium treatment, Thomas says. The rhythmic caterpillar purring has the effect of the queen ant’s noises, not those of a worker, Thomas and his colleagues report in the Feb. 6 Science.

It’s news that a queen sounds different from workers in an ant colony, Thomas says. Ants have such remarkable chemical messaging systems that their noises haven’t received much scientific attention.

“I haven’t been this excited about a paper in a long time,” says tropical butterfly ecologist Phil DeVries of the University of New Orleans. He made the first recordings of caterpillar calls, which he says occur only in groups that have some kind of relationship with ants.



M. rebeli caterpillars make a mini version of the brrrrrr of a woodcock or snipe, Thomas says. Recent work has suggested that caterpillar noises may come from repeated muscle spasms. And when caterpillars become enclosed pupae, they make noises by rubbing a scraper, or plectrum, on their abdomen against a patch of fine grooves called a file. “Actually they can wriggle their abdomen quite a bit,” Thomas says.

Adults of four of the 11 ant subfamilies also make noises by rubbing plectrum and file, Thomas says. “It’s rather like strumming a guitar.” In a quiet room of ants, he can just manage to hear “quite a scratchy sound,” he says.

Advances in miniature electronics made the new study possible. Specially built ant-scale microphones and speakers allowed researchers to record both queen and worker ants under normal conditions and then play back the noises and observe ant behavior.

To a human ear, queens and caterpillars don’t sound at all similar, Thomas warns. Yet ants perceive noises differently, picking up vibrations with sensors in the legs. “There is a debate about how well, if at all, they perceive airborne sounds,” he says.

Bottlenose dolphin shows off her butchering skills

Considering they can't wield a knife or cleaver, dolphins make impressive butchers. Researchers in Australia recently observed a bottlenose performing a precise series of manoeuvres to kill, gut and bone a cuttlefish.

The six-step procedure gets rid of the invertebrate's unappetising ink and hard-to-swallow cuttlebone.

The procedure begins when the dolphin shoos a cuttlefish out of an algal forest into an open patch of the seabed. Next, she pins the cuttlefish down, ramming it into the ground. To rid the body of ink, she uses her snout to pick up the cuttlefish, and then shakes it several times until a black cloud streams out.

Let's walk through that again:

The dolphin begins the routine by shooing a cuttlefish out of hiding

She proceeds to pin it to the sand to kill it


Next, she nudges the invertebrate off the seafloor with her snout

To remove the cuttlefish's ink, which can slow digestion, the dolphin shakes it back and forth


Rubbing the inkless corpse against the sand breaks and releases its indigestible cuttlebone


The filleted cephalopod is now ready to eat!







Success!


Article from NewScientist

Oral sex gene helps male fish fake it

Men may be intrigued to hear that researchers have pinpointed a gene that makes females suck up sperm through their mouths.

The gene was found in the cichlid fish, where the males have evolved a way to lure females close so that they can squirt sperm into their mouths.

As is the case in many fish species, the sight of a brightly coloured male somehow triggers females with ripe eggs to start releasing them. But in cichlids, there is a twist. Females hold their eggs in their mouths and incubate them there after fertilisation - a behaviour that is thought to have evolved to protect the eggs from predators.

As soon as a female has spawned her eggs, she collects them up in her mouth. Normally, sperm released into the water by a male nearby will then fertilise the eggs.

But males of certain cichlid species in east Africa have evolved a way to increase the odds that females take up their sperm. Oval yellow markings resembling the eggs are found on the anal or pelvic fins. When a female approaches the male, she thinks she sees an egg on its fin, so tries to vacuum it up in her mouth - and get a mouthful of sperm from the canny male in the process.

'Turned on'

Salzburger's team believes it has now identified the gene that makes this bizarre mating behaviour possible.

They suspected a gene called csf1ra - short for colony-stimulating factor 1 receptor a, was responsible - because they knew that zebrafish lacking this gene failed to produce a yellow pigment similar to the shade of the cichlid fin spots.

The researchers extracted DNA samples from 19 cichlid species - nine that had egg spots on their fins and 10 that did not. They found the species that had evolved most recently had a mutation in the csf1ra linked to the egg spots.

Salzburger says this shows that the dummy egg spots are a genetic trait that provides a selective advantage because they encourage females to participate in oral mating.

Thanks, NewScientist!

Golden Tortoise Beetle

This Coleopteran is named the golden tortoise beetle because of the resemblance the "shelf" that skirts the outside of the wings and thorax bares to a tortoise. These critters are able to alter their vibrant color within a short time period, turning from brilliant gold to a dull, spotty reddish color. When disturbed, they become orange with black spots. Pretty ferocious.

Tiktaalik your Inner Fish

Evolutionary Oddity: Lungless Frog Found on Island of Borneo

The first recorded species of frog that breathes without lungs has been found in a clear, cold-water stream on the island of Borneo in Indonesia. The frog, named Barbourula kalimantanensis, gets all its oxygen through its skin.

Previously the only four-limbed creatures known to lack lungs were salamanders.

A species of earthwormlike, limbless amphibian called a caecilian is also lungless.

Tetrapods, or four-limbed creatures, that develop without lungs are rare evolutionary events, Bickford and colleagues write.

The researchers suggest lunglessness in B. kalimantanensis may be an adaptation to the higher oxygen content in fast-flowing, cold water.

"Cold water can hold more dissolved oxygen than warm water," Bickford explained.

The frog also has a low metabolic rate, which means it needs less oxygen.

What's more, the species is severely flat compared to other frogs, which increases the surface area of the skin.

"Along with the fact that having lungs makes you more likely to be swept away in a fast-flowing stream—because you would float—this [is] a very strong context for the evolution of loss of lungs," Bickford said.

(taken from google images)

(Article from National Geographic Website)

New Flat-Faced Fish Sighted Off Indonesia

Divers have spotted a new type of fish off Ambon Island in Indonesian waters. The striped fish, which is about the size of a human fist, is believed to be an anglerfish because it crawls along the ground and into crevices using leglike pectoral fins. But unlike most anglerfish, this species does not have a "lure" dangling from its head to attract prey, so it probably represents a family of fish previously unknown to science, says Ted Pietsch, a professor of aquatic and fishery sciences at the University of Washington.

Three scuba divers first spotted and photographed one of the fish in late January. In search of international experts to identify the fish, they found Pietsch, who says the fish is unmistakably an anglerfish because of the leglike fins on its sides. Anglerfish are also known as frogfishes and toadfishes.

The fish's most unusual feature is its flat face. Most fish have eyes on either side of their head, and Pietsch says he has never seen a fish with two forward-facing eyes in his 40 years of studying fish.

The new fish appears to be fleshy with tough skin, because it is able to squeeze itself into very small cracks in coral reefs without getting scratched. That may be how it has escaped human attention for so long.

The divers who discovered the fish kept quiet about it for a while. But now that another adult, two juveniles, and a mass of eggs have been seen, the word is out.

(Article from PopularScience)