Mimic Octopus

Originally published September 8, 2010 (The Manitoban, Vol. 98, No. 4)

Today is the day: back to school. Some of us might be filled with excitement and hope for the thrill of a new year of learning and higher education. Others might be devastated and frightened by the stresses of too many courses and heavy workloads. I am filled with both excitement and dread and the back of my mind is crying out, “I'm not ready!”, but what can you do? Take a deep breath, jump in with both feet and just hope for the best. Perhaps this issue's Z.I. creature of choice can be some form of inspiration to us all. It is the intelligent, industrious, devious and graceful mimic octopus.

The mimic octopus, Thaumoctopus mimicus, was unknown to scientists until its discovery in Indonesian waters in 1998. Mimic octopuses tend to get about two feet long and are a modest brown and white striped sort of colour but like many of their cephalopod friends, they have the ability to change colour by altering the distribution of pigment in their skin. This is a form of communication that can be used to interact with members of the same species or to warn off potential predators. It is also a strategy used to camouflage the animals  and avoid being spotted by predators. Many cephalopods can also modify the texture and consistency of their skin in order to appear flat and smooth like sandy bottoms, or rough and bumpy like a rocky area or coral reef. The mimic octopus takes these abilities to the next level by using a combination of pigmentation and strategic movement and limb positioning to actually mimic other organisms found in its highly diverse environment. 

The mimic octopus imitates many highly toxic animals such as lionfish, flatfish, and even sea snakes. These animals have bold, high contrast colouration that is used to warn potential predators of their toxic nature. The idea for the mimic octopus is that if it can pass itself off as one of these dangerous animals, it will not be chased and eaten by its own predators. Seems like a reasonable thing to do, kind of like wearing those t-shirts with the really buff and sexy body type to fool unsuspecting potential dates at bars, right? The thing is that there is a pretty low risk for humans; if the individual you are trying to fool into going on a date with you realizes that it is not your true buff bod but just a t-shirt, at worst you just won't get a date but, for the mimic octopus, if the poisonous animal imitation is a failure, the mimic octopus gets eaten. Game over.

Surprisingly, scientists haven't yet come up with any really fancy explanations for how this high risk strategy evolved, but there are some fresh ideas going around. New research by scientists from the California Academy of Sciences and Conservation International Indonesia looked at DNA sequences of 35 different species of octopus related to T. mimicus in an effort to shed light on this unique adaptation. Their research suggests that the use of bold colour patterns evolved first in order to shock and frighten potential predators away should the more passive camouflage technique fail. Then, the swimming techniques and arm positioning used to mimic the movements of different species seems to have evolved. Finally, the two appear to have been combined; bold colour patterns while swimming like a lionfish, sea snake, or flatfish, as seen in the mimic octopus today.

This is also the first known example of an organism that mimics multiple different species and what's more, observations have been made of mimic octopuses impersonating the specific type of predator that would be most dangerous to whatever species happens to be threatening the octopus at that time! The high level of intelligence suggested by this strategic mimicry definitely places the mimic octopus in the “smarter than the average bear” category, in this writer's humble opinion.

Much remains unknown about the life history strategies of the mimic octopus. They live on the bottoms of muddy estuarine areas in the Indo-Pacific region and their relatively recent discovery means that there is much more to be learned about these amazing little cephalopods. 

mimic octopus as flounder

Andean Condor

Originally published August 18, 2010 (The Manitoban, Vol. 98, No. 3)

The Andean Condor is the largest raptor in the world. Adults weigh between 20 to 30 pounds and reach a shocking 4 feet in height with a wingspan of up to 10 feet! Condors are a type of vulture and thus feed primarily on dead or dying animals. They will also feed on young or injured animals and raid nests for eggs. Eating is not just a disorganized mess of gut-pulling; the dinner table is remarkably structured with the oldest, dominant male feeding first, followed by all other males, then females and young. Scavenging for a meal by poking your head into rotting carcasses whenever possible is not conducive to good hygiene and this is why the heads of vultures are bald. The Andean Condor may travel over 300 kilometers per day looking for food. They can soar at altitudes of up to 18 000 feet using thermals to save energy. They also save energy by allowing their body temperature to drop several degrees below normal at night. Keeping one's body temperature up to snuff is shockingly expensive. 

Andean Condors are New World vultures that are more closely related to storks than to African vultures. They are the only new world vulture to show sexual dimorphism; the males are larger than females and have big, fleshy crests on top of their heads as well as a white collar of feathers around the neck. Females have bright red eyes. This condor does not have a “voice box” and so is usually silent. They make weird hissing, clucking, or barking type sounds during courtship, at which time males try to impress females by prancing around with their massive wings outstretched. They mate for life and may live as long as 75 years in captivity. Both parents take turns incubating the eggs and raising and feeding their young. Breeding usually takes place every second year (or not at all if food and/or weather conditions are poor) and only one egg is laid. Young do not leave the parents until their second year and do not reach sexual maturity until about 6 or 7 years of age. 

How about a simple mathematical problem to ponder? Assume a 100% survival rate where all young birds survive to adulthood and are themselves able to reproduce. Assume that the point of reproduction is not in fact for pleasure but to replace one's self and spread 'dem lovely genes. If two birds produce one bird every other year, how long would it take to guarantee they replace themselves and thus maintain a stable Andean Condor population? The answer, in a perfect world, is four years and last I checked, it was not a perfect world. Andean Condors have fallen upon hard times. 

The Andean Condor is thought to be hands down the largest flying bird that exists in the world today. What have we got to compete against that? Big brains, pah! Perhaps then jealousy is the reason for this incredible animal's addition to the U.S. Endangered Species list in 1973. More practical reasons might suggest things like over hunting, deforestation, loss of habitat, and pollution. Andean Condors breed relatively well in captivity and many young have been released back into the wild since the 1990s. Radio tracking has shown that many of the released birds have survived to maturity and have themselves begun to reproduce in the wild, yet they are still listed as endangered. 

Andean Condor feathers have been harvested for many purposes: for cigarette holders, warding off nightmares, and by harpsicord makers for...something. Various other body parts have been used by various other people for various other reasons at various times: their bones have been ground to soothe rheumatism, their stomachs have been eaten to cure breast cancer, and their eyes have been roasted to improve human sight.

Now let's all dig out our Much Music Dance mix cds of the 90s and celebrate tentatively. Or you might want to look up the San Diego zoo for more information on their captive breeding and wildlife reintroduction programs.

Dragonflies

Originally published July 21, 2010 (The Manitoban, Vol. 98, No. 2)

Do you remember how much you loved Filmon Fridays when you were a kid? A whole day off school?! Man, it was incredible. What have we got that can compare these days? Lackluster dreams of bringing back the Winnipeg Jets? Perfectly good streets quietly and without fanfare being renamed after football players? Come on, Katz-- I want action. I want novelty. I want good ideas. I want a political platform that includes the introduction of a 'Dragonfly Appreciation Week'.

You might think this a departure from the vision of Zoological Investigations, to write about a common and typically well known animal such as the dragonfly, but there are many wonderful facts about dragonflies that I am willing to bet whole packages of Popeye cigarettes the average person on the street just simply doesn't know. 

For starters, dragonflies have been gracing this lovely old rock with their presence for the last 300 million years! They are thought to be one of the first insects that evolved wings (which are derived from the integument or skin, not the limbs) and the ability to fly. The ancestors of today's dragonfly species had wingspans of 20 to 50 centimetres! Just think about that for a second, will you? Popular belief tells us they were able to grow so freakishly huge because the atmosphere during that period (the Carboniferous) contained way more oxygen than it does today, enabling dragonflies to ventilate such a massive body (no lungs for insects, only spiracles and a tracheal system, thank you). Today there are about 5 000 described species of dragonflies and their close relatives the damselflies. 

 

Next up on the list of Odonatous wonders: those four lovely wings. They can beat them synchronously or individually, allowing such elegant flight maneuvers as hovering, taking off backwards, unbanked turns, rapid acceleration (up to nearly 40km/hr) and basically as far as flight goes, they just own the sky. They can fly in tandem while mating, kind of like those crappy love scenes in the old Superman movies. Dragonflies have compound eyes made up of repeating units of a simplified visual receptor called an ommatidium. They have up to 30 000 ommatidia per eye that receive light from whichever direction they are pointing in, giving them an almost 360 degree viewing field. Their vision is binocular, allowing them to judge distances accurately and they see in colour (except red), UV, and detect polarized light. The eyes are also highly sensitive to motion and can detect movements separated by up to 1/300^th of a second, which would make watching a movie look like a series of still photos. The main downside to this masterpiece of an idea is that because the focus cannot be changed near images appear blurred but with all those other great features, who cares? Most things tend to look worse up close anyhow, except perhaps lady dragonflies. 

 

As most of us know, dragonflies are voracious predators of other insects in the adult stage, but they are also magnificent killers during their juvenile, or nymph phase of life, which can last anywhere from months to several years in different species. Dragonfly nymphs hang out in the water, eating most anything they can catch with their big, nasty extensible jaws (think Alien). They've even been known to bite humans. They breathe through gills in their rectum, which makes me giggle but don't get me wrong, I respect the hell out of dragonflies. On the subject of rectum, the nymphs can propel themselves suddenly by rapidly ejecting water out of their anus, like some kind of super-fart sneak attack.

Is this sampling not enough to convince you of the merit Dragonfly Appreciation Week holds? Well, dragonflies are all over the place in folklore because they are historically known for being super badass and way cool. In Romania, dragonflies were said to be horses possessed by a devil and in Sweden, folklore states that the devil uses the dragonfly to weigh people's souls. With the number flying around in my backyard these days I can't tell if it's a good or a bad sign, but I am a bit nervous after hearing that one.

Dragonfly larvae are aquatic

Adult dragonflies are not.

Northern short-tailed shrew

Originally published June 23, 2010 (The Manitoban, Vol. 98, No. 1)

Hello again readers of the Manitoban and welcome to late June. It is just about that time to start planning your doom — I mean future — for this fall and what better way to get back into the swing of things but by learning a little about something even smaller and more insignificant than most of us generally think ourselves to be. Let us examine Blarina brevicauda, the northern short-tailed shrew. This little buddy is only about 120 mm long and weighs no more than 30 grams.

Whilst backpacking about the scenic Canadian countryside this summer, you might expect to meet Blarina in any one of the southern parts of the provinces, from breathtaking Saskatchewan all the way east to balmy Nova Scotia. As usual with any summer vacation, it is best not to get too friendly with strangers, especially considering the Northern short-tailed shrew is the only poisonous mammal in North America.

These shrews use venom produced by the salivary glands along grooves in their teeth to subdue their prey, which are primarily invertebrates but also include small mammals and amphibians. The venom keeps the prey alive yet immobilized for convenient, hassle-free meals. Shrew venom contains both neurotoxins that cause paralysis as well as hemotoxins that prevent blood clotting, destroy red blood cells and generally make a big mess out of the internal organs. One “highly reliable” source — Wikipedia — states that the venom of Blarina brevicauda, when intravenously injected, is enough to kill 200 mice. What kind of mice and how many died in quest of that most valuable information remains a mystery to me.

In general, shrews are small, terrestrial mammals that forage almost continuously for food to satisfy their raging metabolic needs. They must eat up to 90 per cent of their own body weight each day in order to survive, especially in the frigid wasteland us Winnipeggers call home. In fact, these little buggers are so dedicated that they don’t even bother to hibernate. They just run around like mad all winter in a desperate search for food.

Next to eating, the shrew’s favourite pastime is, you guessed it, sex. Females can have up to 10 litters per year, assuming they manage to survive that long. Shrews live to around 30 months of age but just over 10 per cent of individuals manage to make it past their first year. They have poor vision but excellent senses of smell and hearing. In fact, our friend Blarina uses a form of echolocation — just like your friends the bats and whales — in order to travel speedily along the burrows it digs under grasses and packed snow. The only other terrestrial mammals known to use echolocation are tenrecs but you’ll have to look them up for yourself because this is usually just a one-animal-per-issue kind of deal.

It turns out that shrews and I have a lot more in common than I thought. But I still don’t know what the hell Shakespeare was talking about!

Valentine's Day Double Feature

Originally published February 10, 2010 (The Manitoban, Vol. 97, No. 21)

Kissing Bugs

Rhodnius prolixus is one of several species of blood sucking insects belonging to the order hemiptera that can be found from southern Mexico to northern South America. With strong jaws, a powerful bite, and sucking mouthparts specialized for drinking blood, this fiend also produces and secretes proteins into the wounds it makes that function to increase blood flow to the wound site. This allows the animal to get more blood more quickly (kind of like pulling up at a drive-thru and ordering extra-large...or maybe it's more like holding up the drive-thru). 

"So the jerks drink blood, but why call them kissing bugs", you want to know. The clever little devils get the name because they often bite humans and other victims such as cats, dogs, rats, and other hapless mammals on the lips or face (and while they're sleeping to boot). However, unlike your typical fantasy Romeo (or Juliet, or Prince Charming, or Ted Bundy, or whoever), these six-legged freaks also defecate as they kiss (bite). The wound swells, becoming itchy and irritated, and what do you do? Exactly what you shouldn't you fool, which is to scratch the damn thing and rub poop all into your love-bite. Aside from being totally gross (and this is really important, especially if you are planning a budget South American holiday this "spring break"/"reading week") these kissing bugs are discourteous enough to leave you with a little surprise in their fecal matter that goes by the name of Trypanosoma cruzi, perhaps better known as Chagas disease or American sleeping sickness. 

Once infected with this flagellated¹ protozoan parasitic disease you might at first notice only swelling around the wounded area, perhaps a bit of fever--in short, nothing much to write home or see a doctor about. Yet things get sinister once chronic symptoms start to develop: malformation and inflammation of the intestines and heart, and damage to the nervous system occur. There is not yet an effective cure for Chagas disease but there are also educational programs and vector control measures (i.e. spaying insecticides) in place where Chagas disease is common.

R. prolixus gets a pretty bad rap overall, what with killing thousands of humans each year and causing much pain and suffering, but there is something to be admired in an animal so stealthy and ingenious as this one. At least, this writer thinks so. 

If you are planning a holiday this winter, keep in mind that a date with Rhodnius is kind of like having unprotected sex with a stranger folks; there's no telling how much trouble you might get into--so pull down your mosquito net, buckle your pants up extra tight, and watch out for that bad old Rhodnius this Valentine's day!

¹ A flagellum is kind of like a tail.

Venus Flower Basket

The stunningly beautiful venus flower basket is nothing like a kissing bug. The venus flower basket, Euplectella aspergillum, is a type of glass sponge that lives anchored to the sediments in deep ocean waters anywhere from 40 to 5,000 metres deep in the tropics of the South Pacific. It belongs to the class of sponges called Hexactinellida because its skeleton is made of long filaments of silica called spicules that have a six-pointed radial geometry. 

The fine silica fibres produced by Euplectella are of particular interest for fibre optics research because of their ability to transmit light in a similar (but superior) fashion to that used in modern telecommunications fibre optics. Commercial fibre optics require manufacturing under high temperatures but because the glass sponges create fibres under lower temperature they contain ions such as sodium that enhance their fibre optic properties, something we humans haven't yet figured out how to do. The fibres of the sponges are stronger than those used in modern fibre optics as well. The construction of the sponge is also of interest because of the unique arrangement of the fibres, which are laid down in concentric horizontal, vertical, and diagonal layers of varying thickness (from nanometres to centimetres). The result is an incredibly strong but delicate frame that is highly resistant to cracks and breaks. 

Fibre optics might only romantic in the form of those flashy Valentine's cards and construction workers might be sexy to some, but I'll bet their bosses (the ones who nerd about on computers and in labs with sponges looking for stronger ways to erect office buildings) aren't, so why are you reading a Valentine's special on Venus flower baskets and what am I talking about? Shrimp. And I don't mean those cheap rings you get from Safeway.

While Euplectella is busy growing up into a strapping young adult sponge, a young pair of shrimp belonging to the family Spongicolidae sometimes move into the base of Euplectella's cone as it grows. The shrimp graze on particulate food matter that the sponge wafts in through it's flagellated (there's that word again) water chambers, do a bit of cleaning, and generally just loaf about, happily in love. Euplectella keeps growing, and eventually a covering or cap is formed at the top of the cone, trapping the shrimp within the sponge. 

Nonplussed, the happy couple proceed to mate and release their young larvae, which are small enough to fit between the latticework of the sponge, out into the great blue deeps. A mated shrimp pair thus spends their entire life within the sponge and for this reason, Venus flower basket carcasses were traditionally given as wedding presents in Japan and the Philipines, to symbolize either eternal love, eternal imprisonment, or both!

Pangolins

Originally published January 27, 2010 (The Manitoban, Vol. 97, No. 19)

Ever wake up in the morning and just ask yourself, "Why"? This volunteer science writer does not profess to have all the answers to that question by any means but, I do think that one of them is the possibility of someday meeting such animals as those I write about and others that you only dream of. For this week, we aspire to meet the pangolins.

There are only eight extant species of pangolin (most of which are endangered), four in Asia and four in Africa. While not actually related to anteaters, they are also called scaly anteaters because, similar to anteaters, they are edentate (lack teeth) with long tongues (up to 16 inches in larger species) and have strong, thick claws used to burrow for insects such as ants and termites. 

They produce a special sticky mucous from salivary glands on the tongue to help catch and trap wily insects. Where to put this grossly elongated tongue you ask? Well, it retracts right down into the abdominal cavity near the pelvis! Without teeth to chew up ant-y food, the pangolins have developed a gizzard-like stomach (as seen in birds), ingesting small stones and sand to help grind their meals once inside the stomach. They have excellent hearing but do not have external ears, and they have a well-developed sense of smell.

Several species are arboreal, some live in burrows and almost all species are nocturnal. Many arboreal species, such as the tree pangolin (M. tricuspis), have strong prehensile tails which they use when climbing. The giant pangolin (Manis gigantea) of Africa can grow to five feet in length and is too large to climb trees. 

These crazy mammals are most notable for their complete covering of overlapping, armored scales made of keratin, that same material responsible for human fingernails. If threatened, pangolins roll up into a tight ball with the head tucked under the tail. They have well developed muscles which makes them very hard to pry apart and the outer edge of the scales are very sharp, so you would not be wise to attempt to unroll an upset pangolin. If that isn't convincing enough, they also have anal scent glands that produce a noxious odour, similar to our North American friends, the skunks (but again, no relation). 

Pangolins are secretive and solitary and not much is known about their reproduction, but they are placental (eutherian) mammals, as are humans, and give birth to between one and three young at a time (most give birth to just one but it depends on the species). Young are born with soft scales that take a couple of days to harden. Young survive by hanging on to the mothers tail or back, or remaining in the burrow for several weeks, depending on the species. If danger approaches the mother will tuck up the baby under her belly as she rolls up, protecting them both.

The first pangolins known in the fossil record are from the Eocene period, about 50 million years ago. For comparison, the first recognizable Homo sapiens showed up about 200 000 years ago.

Oxpeckers

Originally published January 13, 2009 (The Manitoban, Vol. 97, No. 18)

That’s right I said oxpecker and no, I am not just gearing you up for Valentine’s Day folks, I am talking about birds. Vampiristic birds! What a way to get back into the swing of things, waking up and going home in the dark while the sun rises and sets with you stuck behind four walls that are most probably very insufficiently punctured by windows. 

Speaking of puncture, the oxpeckers belong to the family Buphagidae and are considered distant evolutionary relatives of the mockingbirds, thrashers, and starlings. There are two species, Red-billed and Yellow-billed oxpeckers. Native to Africa, they make their living primarily by hitching rides and feeding on large hoofed mammals such as wildebeest, impala, giraffe, rhinoceros, water buffalo and others. 

Oxpeckers feed heavily on parasites living off mammalian blood and tissues. They especially enjoy ticks but will also eat lice, mites, fleas, small insects and other organisms attempting to lodge within open wounds. They will also consume dead skin cells. Once thought to be a symbiotic relationship, with mammals benefiting by removal of the external parasites and birds benefiting by a nutritious (albeit disgusting) meal, that viewpoint no longer so certain. 

Instead, it may be that the oxpeckers are themselves a type of parasite. There are many observations of these birds actively feeding on the blood of their host mammals. Observations have been made of oxpeckers actively keeping wounds open, of using their bill to exert pressure around wounds to increase blood flow, and of drinking blood from wounds made by ticks without consuming the ticks themselves. Observations of the birds inflicting wounds themselves are apparently some combination of absent, rare, and/or unreliable. 

While some evidence exists to show that oxpeckers can actually weaken and stress their mammalian hosts by keeping wounds open, they also keep wounds free of bacteria and other infectious agents; so, while they may be riddled with open sores, they are at least clean sores. Most animals tolerate the oxpeckers, and many have learned to respond to oxpecker alarm calls and thus gain protection in the form of an early-warning system for predators. Not all of our hoofed friends appreciate these offers however; elephants and some species of antelope actively and effectively avoid, resist, and remove the oxpeckers from their body.

What is certain is that oxpeckers rely heavily on large African mammals. They feed, sleep, court, and even mate on their backs, and use their hair and dung to build nests. They also eat ear wax!

Red-billed Oxpecker

Yellow-billed Oxpecker

Antarctic Icefish

Originally published December 2, 2009 (The Manitoban, Vol. 97, No. 16)

It is written (at least it is now): "As you sow procrastination, so shall you reap procrastination…" You should be glad to know, if you haven't guessed already, that I am procrastinating. Right now. Sacrificing valuable study time and perhaps even entire letter grades to tell you about yet another of the under-appreciated creatures inhabiting our planet. I suggest you return the favour (and fulfill the italicised proverb above) by procrastinating about your own studies in order to read this.

Winter is coming and we can learn a lot from the icefish. If you want to impress your friends, I suggest you refer to them as Notothenioids, which is the suborder they belong to. If you'd like to refer to them as a family call them Channichthyidae, but just make sure you can pronounce this stuff before you go making a fool of yourself over it. 

 

There are over 120 described species of icefish living in the frigid Southern Ocean waters surrounding the Antarctic. These fish are primarily benthic (they live on the bottom) and all lack a swim bladder (that thing that helps other fish move vertically in the water column). Buoyancy is instead regulated by deposition of lipids in the tissues, by reduced ossification of bony structures, and reduction in the amount of skeletal elements they possess. 

Icefish are able to survive in the below freezing Antarctic waters (-1.5 to -2.0 C) that are not frozen thanks to salt. How do they do this you ask? Well, I am glad you asked because that is the second neatest thing about these fish. Their body fluids have antifreeze proteins in them that bind to ice crystals, should they begin to form, and prevent them from spreading throughout the body. 

The first neatest thing about icefish is that they have no erythrocytes (red blood cells) or hemoglobin in their blood (you know that protein that carries oxygen to your starving tissues? No big deal...). Aside from being a great statistic to brag to your distant evolutionary relations about--they are the only vertebrates in the world that don't make hemoglobin--it looks really cool because without hemoglobin, blood is colourless! How do they get away without hemoglobin? This is made possible by one of the many mysterious and wonderful properties of water: cold water has higher concentrations of dissolved oxygen, allowing the icefish to meet all their oxygen needs through the skin and at the gills. If only life were so easy for us frigid, pathetic humans, just waiting for the big freeze. 

At least there's hockey to look forward to over the next 6 months!

Caecilians

Originally published November 11, 2009 (The Manitoban, Vol. 97, No. 13)

While my long-term goal as a volunteer science writer does include developing a ravenous cult following at least the size of Winnipeg, I am not yet so megalomaniacal as to expect that just 5 articles spanning 3 months will have generated a base of regular readers. However, just in case any of you happen to be riding on the leading edge of my wave (so to speak), I want you to know that I really wish this article hadn’t taken so long. The thing is…I really wanted to talk about Archelon but to my utter dismay, I just couldn’t find enough information. 

This is what I could find out about Archelon: Archelon was a marine turtle alive during the late cretaceous period 80-odd million years ago that looked pretty similar to marine turtles alive today with the exception that it was the largest turtle that ever existed (as far as we know). 

Archelon was the size of a small car, but bigger than a Smart car because they don’t count.

So without further ado, I will now talk about caecilians because they are really cool too and they are not extinct. And unlike that nasty trick I pulled last time, they are not about to become extinct (largely because most of them live underground and no one really knows very much about them and with the exception of one species that is in fact endangered). I also won’t include any bad jokes about Sicilians but this is mostly just because I don’t know any, so if you have some that you find relevant, you can just add them in wherever you like. 

 

Caecilians! They, along with frogs and salamanders, are amphibians. They do not have limbs (i.e. they are legless), they are either aquatic or burrowing, some lay eggs but the majority are viviparous (give birth to live young), and many exhibit parental care. Some caecilians have scales (no other living amphibians have scales as far as anyone who’s talking about it knows) and all caecilians have tentacles, which are likely an adaptation to living under low-light conditions.

Some structures that are associated with eyes in other vertebrates are instead associated with tentacles and the eyes, which are reduced or even covered with thin flaps of skin, are located on the tentacle itself in some species. They are thought to have a chemosensory (“smelling”) function. Roughly 75 percent of known caecilian species give birth to fully formed young that may be between 30 to 60 percent of their mother’s body length (yikes). 

Initial growth of the fetus is supported by a yolk but this is used up before development has completed, meaning the remaining energy needed has to be supplied internally by the mother. Nutritious materials and secretions are scraped from the walls of the mother’s oviducts with specialized teeth! In caecilians which do lay eggs, the female often broods and guards the eggs until they hatch. 

If you are a geek like me and think that David Attenborough is just the cat’s meow, you may be familiar with a newish series called Life in Cold Blood. The film crew and science team were able to stick a fancy little camera into a caecilian’s burrow and made a really neat discovery: oviparous (egg-laying) caecilians must provide food for their under-developed young once they hatch and the spy camera found that mother caecilians begin to slough off a specialized outer layer of skin, high in fat and other nutrients, upon which the baby caecilians feed every 3 nights or so! Talk about giving the shirt off your back. 

The young show a 10-fold increase in growth in just a week of this, so even though it might sound disgusting, it is a great way fatten your kids up and get them the heck out of the house (or burrow as it were) already. Be sure to tune in next time for… something else obscure and intriguing and worth waiting for!

Golden bamboo lemur

Originally published October 14, 2009 (The Manitoban, Vol. 97, No. 9)

The golden bamboo lemur, Hapalemur aureus was not formally discovered until the ripe old year of 1987 on that beautiful and mysterious island located off the eastern coast of Africa: Madagascar. This wonderful little primate is typically about 11-18 inches long (not including the 9-13 inch long tail) and weighs an average of only 3.5lbs. It tends to travel in groups of 2-6 individuals, often a male, female and offspring of varying ages. 

The range of H. aureus overlaps with that of two other closely related species--the greater bamboo lemur, H. simus and the grey bamboo lemur, H. griseus. All three species eat, as their name implies, bamboo. But let's get specific; these lemurs eat from the giant bamboo known in Latin as Cephalostachyum viguieri so just try saying that one 5 times fast. Go on, try it... 

"Who cares what the damn bamboo is called! I've got more important things to do, like studying or procrastinating about studying!" you very likely have just exclaimed in a fit of rage over your pronunciative failure. But you should care about what the bamboo is called, because it is full of cyanide! The giant and grey bamboo lemurs eat from parts of the plant which are very low in cyanide (safe doses like in almonds) or from which cyanide is virtually absent. But the reason I am writing about little buddy the golden bamboo lemur is because it eats primarily the fresh young shoots of the giant bamboo, which are just chock full of cyanide. 

Cyanide is really interesting to talk about all on its own, but for now let's just consider that it works by preventing the uptake of oxygen by the blood...spooky. Some enthusiastic researchers (Glander et al. 1989.) observed the golden bamboo lemur to eat roughly 500g of bamboo each day, and then they did some fancy math based on weights and lethal dosages and found out that our friend H. aureus is eating approximately 12 times the lethal dose of cyanide just like it was a bowl of ice cream and you skipped dinner. Not even a belly ache! And how do they do it? Nobody knows!

Well, winter is coming, and most Winnipeggers hate winter. Why live in a province that spends at least 6 months of the year deep in miserable, "I don't wanna go outside, it's too cold and depressing and the city can't get it together to plow the freakin' sidewalks in a timely fashion" winter? That answer I don't have but what I will leave you with for this edition is a bleak thought to nurse along with all the other bleak thoughts of winter you will probably be thinking soon enough: the golden bamboo lemur is now classified by the IUCN (International Union for Conservation of Nature) as endangered. The major reason for the decline in H. aureus numbers is thought to be a result of "slash-and-burn" agricultural practices, i.e. habitat loss in the form of deforestation (derainforestation?). The only known populations according to the IUCN are found in two of Madagascar's National Parks and a small captive breeding program for golden bamboo lemurs was in place until recently. Woah, bummer. Sorry friends.

Australian red-backed spider

Originally published September 16, 2009 (The Manitoban, Vol. 97, No. 5)

Last night I had to come to terms with two things: I’ve got a mean bronchial infection and there are spiders gleefully using my bathroom as their breeding ground. I counted at least ten spiderlings who’ve built their first tiny webs in various nooks and crannies of the room as I was brushing my teeth. It was somewhere at the count of around eight that I started to think about the number of eggs female spiders usually lay, and from that point I was forced to ponder the potential success rate of hatchlings in an environment without predators of any sort. Lucky for me, my bathroom isn’t very big and I think space might be a limiting factor. Maybe those babies are eating each other.

Now one or two spiders I don’t mind, in fact it is my sincerest hope that they will eat the fruit flies that are having a heyday in the beer empties. Ahem. Regardless, I pulled out my Golden Guide to Spiders and Their Kin pocketbook and quickly decided that it was impossible for me to judge with any sort of accuracy what type of spider these are. Admitting defeat, I thought back to a really cool (and probably much more interesting) spider I learned about last year: Latrodectus hasselti, the Australian red-backed spider.

A close relative of the infamous black widow spider, red-backed spiders can be found throughout most of Australia, as their name implies. Females are about one centimeter long with a pea-sized body and males are much smaller, 3-4 millimeters. Only females build webs, and only the bite of the female is dangerous to humans (anti-venom is available). The lifespan of males is only about 6-7 months, while females average 2-3 years. It is most likely this discrepancy in both size and lifespan which leads to what I, and numerous biology textbooks, think is the most interesting thing about this species—it’s reproductive behaviour. Male redbacks who go a-courtin’ are at serious risk of being eaten by their potential mate before they have a chance to get the job done, so they approach very carefully, using spidey-signals to announce themselves. The male begins copulation by inserting sperm via one of his two palps into the female genital opening. This being done, the male performs a backwards summersault, palp still inserted, and lands with his abdomen in front of the female’s nasty, venomous jaws. She begins secreting digestive juices and eating her partner’s abdomen almost instantly. The male, still alive, attempts to continue the courtship ritual and to insert his second palp (with sperm) before his inevitable death. This folks, as it is affectionately called by some, is sexual suicide. Holy cow.

So on that note my happy, lovesick readers, I shall now spend some quality time rounding up spiders down in the bathroom. I really shouldn’t let this situation get out of hand like I did with the fruit flies. See you next time!

Tuatara

Originally published September 9, 2009 (The Manitoban, Vol. 97, No. 4)

Ah, New Zealand. That dreamy cluster of islands that friends or maybe friends of friends of yours have burned up precious student loan dollars visiting during spring breaks and summer vacations. New Zealand has drifted through millennia of isolation during which time evolution ran amuck, creating a shocking array of birds and reptiles the likes of which we North Americans have only dreamed of through the months and months of cold winter nights alone — at least, this fine scribe has anyhow — but what I am really trying to write about is the ancient (and endangered) creature I hope to enthrall you with in this installment of Zoological Investigations: the tuatara.

Tuatara are reptiles, but not lizards. They belong to a related group, Sphenodontidae, which flourished during the Mesozoic period some 250 million years ago. Today, the only extant members of this group still in existence are the tuatara!

There are only two species, Sphenodon punctatus and S. guentheri, which once roamed gleefully throughout the North and South islands of New Zealand but were wiped out on the mainland with the introduction of mammals and now survive on just a handful of surrounding islands. With numbers as low as 400 adults, S. guentheri is currently battling against extinction while S. punctatus is thought to boast only 50,000 individuals.

Some of the features which make the tuatara such an interesting animal to learn about are also contributing to their current decline. For example, tuatara can live 60-100 years and do not reach sexual maturity until 15-20 years of age. Males do not have a penis but transmit sperm to the female by positioning the shared opening of the reproductive and excretory tracts, the cloaca, close to that of the female (most birds and many other reptiles do it this way, too, except turkeys — they’re crazy). Females only become sexually receptive every 2-5 years (bum luck, huh?) and once their eggs are laid, no care is provided for the young. The eggs take between 11 and 16 months to hatch, which means there is a lot of time for things to go wrong!

Adults are nocturnal and feed on almost anything they can find, including invertebrates, eggs, birds and young tuatara! For this reason, juveniles are active during the day. Tuatara are found in close association with nesting shore birds because they inhabit burrows made by the birds and because the bird guano, or feces, attracts delicious insects.

Perhaps the neatest thing about tuatara is their third eye! Unlike the yogis of the East, the third eye of the tuatara is visible below the skin on top of the head and contains a lens, retina and nerve connections to the pineal gland (which influences sleep and hibernation). The function of this organ is debated but some scientists believe it is used to regulate behaviours based on light and temperature signals.

If you would like to see a tuatara in your lifetime, you can fly to New Zealand for less than $2,000 CAD. Don’t ask me how you’re going to get home, though!

Nudibranchs

Originally published August 19, 2009 (The Manitoban,Vol. 97, No. 3) 

Zoological Investigations

with your inevitably charming host, Mace Detective!

              Welcome, welcome, my literate learners, to the first in a series of exhilarating articles designed to delve into the wild and expansive realm of the lesser known and oft ignored members of kingdom Animalia. No stone will be left unturned as I, your journalistic host, solemnly vow to thrill your synapses with news of the humble exploits and existences of many contributors to life here on Earth.

 Today, I would like to draw your attention to the creatures known as nudibranchs. The word nudibranch means naked gills, in reference to the fact that nearly all of the nudibranchs have unprotected, external gills. Once grouped with the sea slugs, these amicable marine gastropod molluscs have recently been awarded the Linnaean distinction of being placed in their very own order, Nudibranchia. There are over 3000 species of nudibranchs grouped mainly as either Dorids or Eolids.    

 Nudibranchs are hermaphrodites, meaning that individuals possess both male and female reproductive organs. Mating nudibranchs engage in simultaneous, reciprocal reproduction where each fertilizes the other. Go ahead, take a moment to imagine that! They vary from 0.79 to 24 inches in length, are carnivorous, and usually venomous.

The Dorid nudibranchs feed mainly on poisonous sea sponges and can store the sponge’s toxins for use in their own self-defence. The Eolids frequently possess cerata—thin, tubular extensions of the digestive gland that run along the dorsal surface of their body. Members of this group have no gills, relying on gas exchange across the surface of their cerata, which are highly folded to increase the surface area available for this type of respiration.

Eolids feed primarily on Cnidarians such as jellyfish, anemones, and corals. Cnidarians possess defensive stinging cells, or nematocysts, which can inject extraordinarily painful poisons into all who stand in their way. Incredibly, Eolid nudibranchs have the ability to digest the stinging cells of their victims whole, passing the cells intact through the digestive gland to the surface of the cerata, where they are incorporated for use in the nudibranch’s own defense. Nematocystic theft!

Other nudibranch species have a symbiotic relationship with algae that live in the surface layers of their skin. The nudibranchs rely on the sugars produced by the algae during photosynthesis to meet their own dietary needs. Solar power!

One of the most exciting things about nudibranchs is their amazing, electric colouration and psychedelic patterning. Blazing blues, purples, reds, yellows, greens, whites and blacks; spots, stripes, swirls and decorative projections make these animals look like something out of a science fiction novel. These crazy molluscs are truly something wonderful—so check them out!