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Behold Aplysia californica–an extremely large sea slug which grazes on red algae along the California coast. The mollusk is rarely found at depths deeper than 20 meters. It grows to seventy-five cm (thirty inches) in length and weighs a whopping 7kg (15.4 lbs). Aplysia californica belongs to a family of sea slugs known as the sea hares –so called because the two rhinophores (smelling organs) atop the creatures’ heads are fancifully said to resemble a rabbit’s ears.
Although this Pacific gastropod is interesting in its own right, the slug is of greatest importance to humankind as a research animal (like the regenerating axolotl). Aplysia has only 20,000 neuron cells–as opposed to a human brain which contains between ten and a hundred billion–and the slug’s neurons are extremely large. This allows neuroscientists to easily observe and assess physiological and molecular changes which take place in the cells when the slug learns something. Aplysia research is thus at the cutting edge of neuroscience. Nearly everything we know about the molecular basis of memory and learning started out as research with the humble gastropod.
A news piece on CNN today featured Dr. Eric Kandel of Columbia University who won the 2000 Nobel Prize in Medicine & Physiology for neural research (mainly on these slugs) and made immense headway on what is probably the great cellular biology mystery of our time. It is a pleasure to see a science article on CNN online but it was also somewhat dismaying to see how many comments were basically “why are we wasting money on studying slugs?” In case it is not self-evident why we are trying to discover the fundamental molecular mechanisms of memory and cognition, here is a brief and not-at-all comprehensive list.
Understanding these underlying biological processes would probably help us find therapy for neuro-degenerative disorders (such as Parkinson’s disease, multiple sclerosis, and Alzheimer’s disease). It might also allow us to comprehend a number of psychiatric conditions, such as schizophrenia and depression. At some point in the future, understanding the molecular basis of memories and thoughts might also allow for the engineering of some sort of bioimplant for the nervous system. You could learn Sanscrit by popping a chip in your head or record your nightmares via wire! Beyond such science fiction concepts, knowing about how the brain works is an end into itself—understanding the most complicated known structure in the universe is a necessary step to building structures of greater complexity.
Although perhaps the politically polemicized commenters who object to studying the sea hare actually reject the creature’s sex life–which is indeed somewhat at odds with traditional notions of romance and propriety.
Like all sea hares, Aplysia californica is a hermaphrodite with both male and female reproductive organs. Because of its physiology it can (and does!) use both sets of organs simultaneously during mating. Multiple Aplysia have been known to form chains of more than 20 animals (somewhat like pop beads) where each animal simultaneously acts as a male and female at the same time with its fore and aft partners. Copulation lasts for many hours (or sometimes for days). One can see how the creatures’ amorous predilections might not sit well with puritans and fundamentalists, however for providing a window into molecular neurophysiology we owe this gentle sea slug a big round of thanks.
My sincere apologies for being such a truant blogger last week! Not only did I fail to post any new articles since Tuesday, I unpardonably left you stuck with nothing but the flimsy Ms. Perry during that time. In order to apologize, allow me to take you on a trip to the island continent of Australia…15 million years ago during the Middle Miocene. During this time one of the largest birds ever lived across Australia: a giant fowl named Bullockornis.
Bullockornis was a 2.5 meter tall (8 foot 2 inch) gooselike bird. The creature weighed in at approximately 500 kilograms (1100 pounds) and scientists believe it was actually related to the modern geese and ducks. If you have ever met a modern goose, you will realize that a goose the size of a bear would be a formidable creature indeed. Additionally Bullockornis possessed a razor sharp beak with immensely powerful jaw muscles. It is hard not to imagine the giant bird nipping off a he-man’s arms like corn kernels or biting through bridge cables with this monstrous beak, but the truth is scientists don’t know what the bird used it for. The monstrous goose could have been a hunting carnivore (like certain ducks are today) or an herbivore which grazed on heavy dense plants. Perhaps, like contemporary geese, it was an omnivore which hunted, grazed, and opportunistically scavenged whatever it could get.
Bullockornis was discovered in 1979 but it only became well known when some PR savvy writer christened it the “Demon Duck of Doom” (which strike me as a silly 1930s Disney-style name, but I guess whatever gets people involved in paleontology is good). The scientific name “Bullockornis” means “bullock-bird” but, even though the bird was the size of an ox, it is actually named for Bullock Creek (a rich fossil location in the Northern Territory). Bullockornis was not the only giant of the Miocene in Australia. The Bullock Creek fossil beds also contained fossils of Giant horned tortoises, marsupial “lions” (i.e. thylacoleonids) and grazing Diprotodontids—giant wombats (although nothing so large as the mighty Diprotodon which evolved in the Pleistocene).
Gamma rays have the most energy of any wave in the electromagnetic spectrum (which includes more familiar radiation such as x-rays, radio, and visible light). The wavelength of gamma rays (10 picometers and smaller–which is a subatomic scale) is less than that of any other sort of EM radiation. Such radiation is created in the event horizons of massive black holes and during the destruction of gigantically massive stars. Comic book enthusiasts know gamma rays as the mysterious super force which created and empowers the incredible hulk, although actual cell biologists recognize gamma rays as ionizing radiation–supremely hazardous to living entities.
On Saturday, April 27, the Fermi Gamma-Ray Telescope (a NASA satellite which orbits around Earth) detected a sudden brilliant surge of gamma radiation from the collapse of a super massive star in a galaxy 3.6 billion light-years away. Gamma ray burst travel in vastly powerful beams which are very narrow–an effect which is a result of the shape of supernovae, as illustrated in the picture above. Our old friend Eta Carinae has probably exploded and produced such a burst by now. A gamma ray bust from a nearby Wolf–Rayet would probably fry away life on our planet if it were aimed directly at Earth, but such explosions are increasingly rare as the universe ages. Scientists can monitor gamma bursts from the edge of the universe (i.e. the distant past) but such a powerful event has never been monitored by our modern satellites and observatories from a middle range until now.
As the gamma ray burst fades (and the astronomy community begins to assess the initial data) other observatories will be on the lookout for the next wave of phenomena associated with the supernova. Most of the energy of a supernova explosion is believed to be dissipated as neutrinos (esoteric subatomic particles which react very little with physical matter in this universe). Fortunately humankind now possesses a sophisticated neutrino observatory on the South Pole where thousands of sensors are imbedded within a vast amount of Antarctic ice. In the rare cases where neutrinos interact with matter, they produce a cascade of charged particles which can emit Cherenkov radiation (familiar as the spooky blue glow in a nuclear reactor). Understanding the neutrino signature of such an event would potentially further our understanding of the physical parameters of existence.
Also, a luminous flash of less energetic radiation (x-rays, radio waves, light, and so forth) should be following the gamma ray burst. We understand these parts of supernovae better (since they are visible from many angles unlike the linear gamma ray bursts), but it should still be pretty–and round out our understanding of the full astronomical event.
The Atacama Desert of Chile is the driest place on Earth. The desert is bounded in the west by the Chilean Coastal Range, which blocks moisture from the Pacific. On the east of the Atacama run the mighty Andes Mountains which catch almost all the rainfall from the Amazon Basin. Thus trapped between ranges, the desert receives 4 inches of rain every thousand years. Because of the dryness, people are very sparse in the Atacama: they are found only at rare oases or as desiccated (but well preserved) mummies lying in pits.
The high altitude, dryness, and lack of nearby cities (with their lights and radio waves) make the Atacama a paradise for astronomers. On a mountaintop 8000 feet up on the Atacama side of the Andes, engineers and scientists are working to put together one of the wonders of this age.
The Giant Magellan Telescope (hereafter the “GMT”) will be a miracle of engineering. When it is completed in 2019 it will be larger than any telescope on Earth. The scope is so giant that it will be mounted in a huge open, moving building (rather than the gun-turret-like buildings observatories are traditionally housed in). No organization on Earth is capable of making a mirror large enough for the necessary purposes, so seven immense 8.4 meter mirrors are being used together to create a single optical surface with a collecting area of 24.5 meters (80 feet in diameter). The mirrors are the pinnacle of optics: if they were scaled up to the size of the continental United States, the difference between the highest and the lowest point would only be an inch.
The scope will be much more powerful than the Hubble telescope and take much clearer pictures despite being within the atmosphere of Earth. In the past decade, telescope makers have used cutting edge engineering to compensate for atmospheric distortions. To do so they fire multiple lasers grouped around the primary mirrors high into the atmosphere. These beams of light excite sodium atoms in the sky which fluoresce—creating tiny “stars” of known wavelength, which serve as points of reference for the adaptive optics. The official website of the GMT further explains the mechanism used to counteract atmospheric turbulence once these benchmarks are obtained:
The telescope’s secondary mirrors are actually flexible. Under each secondary mirror surface, there are hundreds of actuators that will constantly adjust the mirrors to counteract atmospheric turbulence. These actuators, controlled by advanced computers, will transform twinkling stars into clear steady points of light. It is in this way that the GMT will offer images that are 10 times sharper than the Hubble Space Telescope.
The telescope is designed to solve some of the fundamental mysteries about the universe. Scientists hope it will help them find out about the nature of dark matter and dark energy (which are thought to make up most of the mass of the universe). Astronomers also hope to find out how the first galaxies formed and (perhaps) to ascertain the ultimate fate of the universe. Most excitingly of all, the telescope should be large enough to peek at some of the exoplanets we are discovering by the thousands. If life exists anywhere near us, the GMT should provide us with compelling evidence in the next twenty years.
The National Science Foundation was initially going to contribute heavily to the telescope but, since the United States Government has become indifferent to science and knowledge, other institutions have been forced to pick up the slack. The scope is being built by a cooperative effort between The University of Chicago, The University of Texas at Austin, The Australian National University, The Carnegie Institution for Science, Harvard University, The Korea Astronomy and Space Science Institute, the Smithsonian Institution, Texas A&M University, & The University of Arizona (so you can probably help out by donating to any of these institutions, particularly the lovable University of Chicago).
Justin Orvel Schmidt (pictured above) is an entomologist who specializes in insect defenses. His greatest expertise is in the stings of hymenopterans—the bees, wasps, sawflies, hornets, and ants (although he also researches the toxic/chemical defences of other arthropods). In the early 1980’s Schmidt attempted to systematize the different medical and physiological effects of insect stings. This work led him to coauthor one of the comprehensive tomes on the subject of insect venom Insect Defenses: Adaptive Mechanisms and Strategies of Prey and Predators. Unfortunately for Schmidt, in the course of his researches, he has been stung/bitten innumerable times by various aggressive and toxic insects (and other creepy crawlies) from around the world.
Based on these experiences, Schmidt attempted to categorize the algogenic (i.e. pain-inducing) effects of hymenopteran stings in the now world-famous Schmidt sting pain index. This index is a captivating blend of subjective pain analysis, horrifying real world experience, and inventive poetry. The lowest sting on the Schmidt index is a 0—betokening a sting which has no effect on humans. The highest rating is a 4 which describes an experience of maddening absolute agony. The index became famous because of an interview with Outdoor magazine. Schmidt has since conceded that his descriptive efforts lack an empirical basis and that stings vary depending on body location and the amount of venom injected. Because of such admissions, Wikipedia took down its remarkable table of stings–which is a shame because the subjective descriptions gave the index its visceral power. Here is a sampling copied verbatim from “Retrospectacle: A Neuroscience Blog”:
1.0 Sweat bee: Light, ephemeral, almost fruity. A tiny spark has singed a single hair on your arm.
1.2 Fire ant: Sharp, sudden, mildly alarming. Like walking across a shag carpet & reaching for the light switch.
1.8 Bullhorn acacia ant: A rare, piercing, elevated sort of pain. Someone has fired a staple into your cheek.
2.0 Bald-faced hornet: Rich, hearty, slightly crunchy. Similar to getting your hand mashed in a revolving door.
2.0 Yellowjacket: Hot and smoky, almost irreverent. Imagine W. C. Fields extinguishing a cigar on your tongue.
2.x Honey bee and European hornet: Like a matchhead that flips off and burns on your skin.
3.0 Red harvester ant: Bold and unrelenting. Somebody is using a drill to excavate your ingrown toenail.
3.0 Paper wasp: Caustic & burning. Distinctly bitter aftertaste. Like spilling a beaker of hydrochloric acid on a paper cut.
4.0 Pepsis wasp: Blinding, fierce, shockingly electric. A running hair drier has been dropped into your bubble bath.
4.0+ Bullet ant: Pure, intense, brilliant pain. Like fire-walking over flaming charcoal with a 3-inch rusty nail in your heel.
While the work lacks rigorous empirical criteria, even the most relentlessly analytical critics seem to aver that being stung by over 150 different species of arthtopods gives Schmidt a certain robust validity. The literary merit of the metaphors is certainly genuine (although one hopes that the good Doctor Schmidt never actually dropped a hair dryer into his bubble bath or let misanthropic vaudevillians torture him with fire). Personally I have only been stung by sweat bees, honey bees, and yellow jackets, so I cannot testify to the more esoteric sting ratings (thankfully–since yellowjacket stings nearly did me in), however something sounds completely right about the yellowjacket sting description. I recall a moment of warmth which metastasized almost immediately into a sour panic-inducing pain which spread through my arm and then my body.
In conclusion, I salute Justin Orvel Schmidt as a man of science and a masochistic poet/performance artist. If he claims that a bullet ant sting is the worst hymenopteran sting, I see no cause to contradict him and I never want to think about it again.
Maria Tomasula is a contemporary artist who paints strange collections of beautiful items coalescing into miniature glowing geometric systems (usually against an empty black outer space backdrop). Dew, flowers, and fruit are the most frequent items in these compositions, but sculptures, amphibians, skulls, mollusks, weapons, and disembodied organs (among other things) also find their way into these little microcosms.
Tomasula paints the shining or dewy objects which make up her still life works with finicky photorealism, yet the abstract structure of the works takes these images towards mathematical abstraction. Her delightful little paintings give us the aesthetics of the natural world as viewed through a dark melting kaleidoscope.
Tomasula has a particular flair for teasing humankind’s magpie-like fascination with shininess and bright colors. From across the gallery, her works beguile the viewer closer and closer. Only when one is next to them does one notice the carnivorous pitcher plants and bird skulls among the velvet, petals, and jewels. However the dark imagery does not outshine the sensuous appeal of these fastidious spirals, loops, and curtains. Tomasula invites us to reach into the dark fractal pattern of beauty to grab the waxy flowers, the moist fruits, the polished gems…if we dare.
Back in 2011, as the space shuttle program wound down, Ferrebeekeeper published what seemed like an elegy to spaceplanes—mixed-use vehicles capable of operating both as spacecraft and aircraft (most notably the space shuttles). The dwindling national interest in science and exploration once seemed to indicate that the shuttle program would be the last spaceplane program for a long time. However, as the United States abandons its interest in cutting-edge Aerospace projects, other nations and private interests are picking up the slack.
Skylon is a British spaceplane concept from a private company, Reaction Engines Limited. During the eighties, Rolls Royce and British Aerospace, poured money and knowledge into the creation of a vehicle named HOTOL (an awkward acronym which stands for HOrizontal TakeOff and Landing). Although huge amounts of human energy went into HOTOL, it was canceled because of lack of funding. Reaction Engines Limited is trying to build on the extensive HOTOL designs.
Skylon certainly has a futuristic look. It has a long slender needle-like fuselage with stubby delta wings sticking out midway. Each of these wings is mounted at the end with a SABRE (Synthetic Air Breathing Engine). These next-generation engines are the real key to achieving single-stage-to-orbit spaceflight (a milestone which has long proven elusive for space engineers). Ideally the plane could take off from a runway and speed up to Mach 5.4 as it left the atmosphere and entered orbit. After deploying its payload it could then glide back down to Earth like a normal plane.
Skylon would be constructed of a carbon fiber frame with heat resistant ceramic tiling and it would employ liquid hydrogen as a fuel to loft its 82 meter long (269 ft) body into near-space (before switching to internal liquid oxygen as it left the atmosphere). Like HOTOL before it, Skylon was stuck in funding purgatory for a long time, but recently a huge chunk of funding became available to test the viability of the various systems. These tests were successfully completed in November of 2012 and Reaction is now moving forward with the building of Skylon.
Skylon is designed to be vastly cheaper than the shuttle or any current rocket programs (and it would cut down on space debris). Engineers estimate that one of the crafts could be ready to launch again in only two days after a successful landing (as opposed to the shuttle which required months of refitting). Let’s hope the technology works out. Although unmanned interplanetary craft are accomplishing great things, it has been too long since there was a flashy achievement
Here in New York the weather outside is February gray. The buildings are gray. The sky is gray. The trees are gray. The people are dressed in gray and black. Fortunately we can beguile away this monochromatic tedium by contemplating the Euglossini, also known as the orchid bees!
Despite their Latin name, the Euglossini are not uniformly eusocial. This means that most species of orchid bees live solitary lives (in marked contrast to honeybees–which live in vast hives more ordered than the strictest totalitarian state). The orchid bees live in Central and South America, apart from one species which ranges into North America. They are notable for their brilliant iridescent blue and green coloring. The females build nests out of mud and resin.
The most remarkable aspect of Euglossini behavior is the male bee’s obsession which the aromatic compounds produced by various tropical orchids. Male orchid bees have a rarified ability to sense these fragrances even in small quantities (like many heady floral/fruit scents the chemicals produced by the orchids are usually complex esters). The bees harvest the molecules with front legs specially modified to resemble little brushes (and in doing so they generally pollinate the orchids, which are wholly dependent on the bees). Astonishingly, the male bees store the chemicals in a cavity on their back leg which is sealed off and protected by waxy hairs.
The male bees appear to use these compounds when trying to attract a mate but no female attraction to the odors has been proved. On the other hand, many Stanhopeinae and Catasetinae orchids are absolutely dependent on the male bees to reproduce. Different species of these orchids rely on specific species of orchid bees to successfully pollinate far-away partners in the rainforest. Charles Darwin wrote about this pollination system after observing it in the wild and later referred to the highly specialized orchids as proof of the ways in which species adapt to their environments.
One of the problems with writing about living things is that there is a lot of troubling news from the natural world. If one writes about the many sad or perplexing issues affecting worldwide ecosystems, people get depressed and stop reading, but if one willfully ignores true problems…well, what is the point of observing and thinking about the world? I remember CNN’s online newspage used to have a Science/Nature header which was so consistently filled with news of species die-offs, ecological disaster, and worldwide blight that the whole science section was canceled. Now CNN has more room for “news” about Ashton Kutcher’s all fruit diet and a tech section with reviews of “cool gear” you can buy for your Superbowl party. Sigh….
All of which is a round-about way of apologizing for today’s upsetting (but extremely important) post concerning the mass die-off of North America’s bats. Wait! Please don’t go to other site to read about “Miley” Cyrus. Bats are actually really important. They are key organisms in ecosystems across the continent. If they all die, the rest of us mammals are also going to be in serious trouble
The culprit behind the bat deaths is a fungus, Geomyces destructans, which causes WNS–white nose syndrome. Despite its cartoonish name, white nose syndrome is a horrible death sentence for most temperate bats in North America. Geomyces destructans is a low temperature fungus (like the hideous specimens you find in neglected refrigerators). As the bats hibernate, powdery white fungus builds up on their little wings and faces. The poor itchy bats are awakened from hibernation and, because of the irritation, they cannot return to a suspended state. The little animals quickly burn up their energy reserves and die—to then become macabre bat-shaped clumps of fungus.
Geomyces destructans seems to have traveled to North America from European caves, probably on the boots or specialized equipment of spelunkers (strange troubled sportspeople who worm deep into the crushing dark of caves). Now that the fungus is in North America, it appears to be spreading by means of bat to bat contact. European bats seem to have a native resistance to the fungus, but American bats are unprepared for it and they have died in legion. Ninety percent of New Jersey’s bats are believed to have already died. As the plague moves to new colonies similar mortality is expected. Although the disease started in the middle of New York State, it has quickly spread along the East coast and it is moving west. Scientists worry that the pestilence could spread from coast to coast (although bats which live in warmer climes might be less susceptible to the low temperature fungus). Bats reproduce slowly—usually at a rate of one pup (or less) per year, so bat colonies cannot replenish like sardine schools or rodent colonies. Additionally the spores linger in caves even after all the bats have been killed.
I personally love bats. I find them endearing and beautiful (and relatable, since I have my own flighty nocturnal habits). Western culture has not been so kind and often equates the flying mammals with witchcraft, Satan, demons, and all other manner of underworld fiends (the Chinese, however, see bats as lucky—in fact one of the Eight Taoist immortals began his cycle of incarnation as a bat). A surprising number of Americans cleave to the old ways and smile at the horrifying curse that jackass cave explorers have unknowingly unleashed on our little chiropteran friends.
This attitude is a big mistake.
Anecdotally, the weather on North America has been worsening. Great storms pound our coasts, droughts scorch the hinterlands, and mighty cyclones appear everywhere knocking down forests. Imagine if, to compound these woes, vast plagues of insects descended upon our homes and crops.
Well, without bats, you won’t have to imagine. Bats are a principal predator of insects—especially nighttime insects like mosquitoes (but also a surprising number of agricultural and forest pests). Humans, being diurnal, underestimate bats, but insect-eating chiropterans eat 80% to 100% of their body mass in insects per night and they live in vast colonies (especially out west). Without bats we are liable to see great swarms of insects eat our crops and we will experience a resurgence of mosquito born ills.
An article in Daily Finance outlines some of the potential fall out of the great North American bat die-off (and if cold heartless financiers are worried about the environment, we know that something is really amiss). So how can we actually help the bats? The Federal government has allocated 1.6 million dollars to study the problem, but this is not a lot of money! Various agencies and organizations are attempting to curtail cave exploration and keep people from becoming a further vector for spreading the fungus. Making people aware of the problems bats are facing is also a useful step (which is why I am writing this). Most of all we need to care for bats before they are gone. Farmers, bankers, politicians, ecologists, and scientists all need to worry about our beleaguered friends. The mass die-off of honey bees has had a horrible effect on agriculture and forestry: the effect of a bat die off could be worse. But even more importantly bats are social mammals—like us. If suddenly 90% of them are dying off, it is a terrible portent as well as a horrible loss to the planet.