Komodo Dragon Spit-It's Aliiiiive!!!

Komodo island monitors are famous for being the world's largest lizard, they can reach three meters in length.  This may seem like reason enough not to mess with them, but you shouldn't be afraid of the dragons, just their thousands of tiny little friends...

Komodo dragons are scavengers and carnivores.  They'll eat most recently dead animals, and will hunt goats, wild boars, water buffalo and even horses and eat them.  But their hunting technique is quite unusual, they will stalk their large prey, then ambush it, not to kill it, but to bite it.  The lizard then simply follows the unfortunate prey around until it dies, either from blood loss or infection.  But what if the animal heals?  Well, this just doesn't happen.

Komodo dragon saliva contains over 50 different kinds of bacteria, once an animal is bitten it is almost guaranteed to develop a bad bacterial infection, a septic wound that will become so toxic it will end their life.

A study of the saliva of both captive and wild komodo dragons was published in the Journal of Wildlife Diseases in 2002.  In part of the study komodo dragon saliva was injected into mice.  One strain of bacteria was present in the blood of mice who died following injection, Pasturella multicoda.  The study stated that many strains of bacteria were isolated in the saliva, "54 of which were known pathogens" and "at least one species of which was highly lethal in mice".  

These findings certainly explain the hunting style of the komodo dragon, but why isn't the deadly bacteria in their saliva a problem for these animals?  Wouldn't a mere scratch to the gum be enough to introduce infection and kill them?  The really interesting finding of the study was that the plasma of komodo dragons contains an anti-Pasturella enzyme, so if the bacteria were to enter the bloodstream, it would be killed.

This fact shows that the giant lizards have evolved with their little friends, so that they can coexist without any danger of infection.  A sinister but fascinating kind of symbiosis!

sources:

Aerobic Salivary Bacteria in Wild and Captive Komodo Dragons

http://www.jwildlifedis.org/cgi/reprint/38/3/545.pdf

Animal Diversity Web

http://animaldiversity.ummz.umich.edu/site/accounts/information/Varanus_komodoensis.html

*This too was actually a post by Liz, sorry again*

Sleepy?

If you catch yourself nodding off in classes, on the bus, or anywhere else, you can probably think of a reason for your condition.  Perhaps you stayed up late studying for an important test, or to watch a movie with your roommate, or spent the night drinking.  But do you really know why your body is telling you to sleep?  What is the true purpose of that irresistible urge to close your eyes and drift away?  Why do we and almost all animals need to sleep?

The truth is, scientists still don't have a clear answer to this question.  They know that sleep plays an important role in memory and that cells function better in a rested person than in an exhausted one, but scientists say that so far as they can tell, animals could have evolved mechanisms to accomplish these things in a waking state, so why sleep?

 

I became interested in this topic after listening to a one of WNYC's Radiolab podcasts, called simply Sleep.  The podcast discussed different scientific ideas about why we sleep and what happens when we do and included some really interesting information on research currently being done to try to solve this puzzle.  One researcher they spoke to, Stephen Lima, is looking at sleep from an evolutionary standpoint to try to understand why animals evolved the need to sleep.  It may seem obvious that animals would evolve to sleep, rest must be good right?  Well, not really.  Sleep makes an animal incredibly vulnerable, it could be eaten while resting, its offspring could be threatened, anything could happen.  There is something about sleep that almost all animals need, and we still don't understand what that is.  According to Dr. Lima, "The fact that sleep is so dangerous is the best evidence that it is necessary, because if it weren't necessary, we wouldn't be doing it.".

 

The evolutionary approach to sleep research is a new one, Dr. Lima states that, "One of the reasons we don't understand sleep is that we haven't taken this evolutionary perspective on it".  The idea is that if we can understand why sleep evolved, we can understand why it is necessary and what it really does.  He and his team of researchers have been watching animals like iguanas, ducks and, yes, fruit flies sleep.  An article published in the New York Times also focuses on Dr. Lima's sleep research, as well as other researchers'.  One discovery they have made that is particularly interesting involves the sleeping habits of ducks.  When ducks sleep in a row, on a log or wherever, the ducks on the ends of the line will sleep with one eye, the one facing away from the other ducks, open.  Every so often they will stand up, turn around and sleep with the other eye open.  Dr. Lima discovered that the reason for this is that the ducks on the ends are only allowing half of their brain, the half controlling the closed eye, to sleep at a time.  The team is now doing research on iguanas to see if they share this strange behavior.  If they do, it will tell scientists that this half-brained sleep probably evolved early in animal evolution, and that early mammals may have been able to do it also, but then lost this ability later in their evolution.  

 

Another model for sleep research is the fruit fly.  A study published in the journal Science in 2006 focused on the sleeping habits of Drosophila (click here for abstract).  It found that the flies needed more sleep after social interaction and couldn't remember tasks taught to them if they were deprived of sleep for a certain period of time after they learned them.

 

This article from the Public Library of Science details a study done in 2006 on zebrafish sleep that found "both striking similarities to mammalian sleep and its regulation and intriguing differences.

This new evolutionary approach to understanding human behavior shows that there's more to phylogeny and systematics than endless debate over the seemingly trivial classification of obscure creatures most people have never heard of.  Hopefully through more research scientists like Dr. Lima will be able to solve more intriguing mysteries about our past, and help us to understand what has made us what we are.  

   

Sources:

http://www.wnyc.org/shows/radiolab/episodes/2007/05/25

(podcast)

 

Jones R (2007) Let Sleeping Zebrafish Lie: A New Model for Sleep Studies. PLoS Biol 5(10): e281doi:10.1371/journal.pbio.0050281

Waking Experience Affects Sleep Need in Drosophila

Indrani Ganguly-Fitzgerald, Jeff Donlea, Paul J. Shaw  http://www.sciencemag.org/cgi/content/abstract/313/5794/1775?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&andorexacttitleabs=and&fulltext=drosophila+sleep&andorexactfulltext=and&searchid=1&FIRSTINDEX=0&resourcetype=HWCIT

 

Zimmer, Carl (2005) Down For the Count.  New York Times 

http://www.nytimes.com/2005/11/08/science/08slee.html?pagewanted=1&_r=1

*This blog says it's by Chicken but it's actually by Liz, who had to sign in as Chicken because she couldn't post as herself... sorry*

The Belgian Blue

In the fitness and selection topic of our course this semester we touched lightly on the Belgian blue and it’s lethal mutation of the gene that codes for myostatin (a protein that counteracts muscle growth). To sum it up this cow has no myostatin, which results in it building mass amounts of muscle and very little fat because the mutation also affects fat deposition.

If you’ve ever lived in Belgium it’s quite apparent that they love their cows. The meat is sold in the butcher section of the supermarkets, never laid out on display like ours, and the posters “Big, Blue, Belgian” are pretty much everywhere. I was actually quite shocked not to be able to find one on the Internet.

They just remind shoppers how good for you the meat is:

i.e.                   No hormones

Less fat

                        Better taste (although I disagree with this because when it comes to a good steak it’s all about the marbling which the Belgian Blue has 17% less of than our normal heifers)

 

Blues also yield 5- 7% more sellable meat than our normal cows at 80% and their carcass is bigger. For some reason they also produce a higher yield of milk. Anyhow, the list goes on and on for the many reasons why these cows are “better.”

 

Why are they not common here?

 

Ignoring most of the English sites on the Internet the truth is that roughly around 80% of these cows cannot give birth to their calves depending on their age. The calves are just too big for their mother’s birth canals. Also the older the mother; the more muscle mass she’s put on, thus she will need caesareans every time she has a calf after being a possible first time successful at a natural birth mom, if she had been that lucky.

 

In September 2001 I spent a year In Belgium on a Rotary youth exchange. I was lucky enough to have spent three months with a veterinarian. I had no idea at the time why he needed two pagers and a cell phone and thought he took his work far too seriously. He hardly ever made it through a full dinner without leaving unexpectedly and woke up multiple times throughout the nights, sometimes more than once.

About eight months into it I finally clued in and happened to be attending a function where he was when of course; he got a call. It took some begging and I had to chug the rest of the bottle of wine for his sheer amusement but he finally let me go with him. (Note: Belgian’s can drink more than you, despite what you may think. They still like to watch us suffer/ enjoy as much as they have)

 

Belgium, which is a tad smaller than Vancouver Island is set up a little differently than Canada. There are small towns everywhere, two big cities and the rest is all farmland. The Blues are EVERYWHERE; in the smaller towns they even sometimes get loose and just wander around the streets until found.

 

After a 10-minute drive at 160km/hr we walked directly into a farmers barn to find our cow. (They HAVE to be at a certain stage in labor before a caesarean can be performed safely.) Since he had been there earlier that morning to check the cow he went straight to work.  The cow wasn’t tied down nor did it even seem to care. He gave about 10 needles straight down its left side by its hind leg and waited 10min. He tested to see if she was numb by poking her with his scalpel and seeing that she was, sliced her open. She didn’t bleed as much as I thought she would. Next he opened the sac the baby was in and pulled it out. After taking the crap off its face so it could breathe he sewed up mommy. What’s scary was the calf was almost as big as me.  The mom just ate hay while I tried not to throw up; the whole procedure took about 20min. We were back at the function in no time and hardly missed anything, except more drinking.

 

This vet who shall remain nameless performs roughly one caesarean a day on average but more like none some days and up to four on others. He charges 50- 150 euros depending on the relationship with the farmers. And those calves are worth 500- 1000 euros each, so it’s worth it for the farmers.

 

Warning: the blood is just the amniotic fluid.

Here is a video of a Blue caesarean:

http://www.youtube.com/watch?v=JPY9sH_MU5w

When I watched it live it didn’t need two people: note the time. Also take into account the retarded people whose comments imply that this is cruelty. Cruelty is letter the mothers body kill the baby when she can’t give birth; then the dead baby killing the mother.

 

The Dairy site:

http://www.thedairysite.com/breeds/beef/8/belgian-blue/overview

 

Info. On the Blue:

http://www.kuleuven.be/cwte/viewpic.php?LAN=E&TABLE=DOCS&ID=17

 

It's the end of the world as we know it...

Throughout the history of the earth the global climate has been punctuated with alternating periods of greenhouse warming and cooler "icehouse" phases. Researchers from the universities of York and Leeds have recently concluded that extinction rates are much higher during greenhouse phases of global climate. By comparing 350 million years worth of data from the fossil record on estimated temperatures and the levels of diversity in marine and terrestrial life, researchers have predicted that if global temperatures continue to rise we may be approaching a climate associated with past mass extinctions. Pollution and greenhouse gases are accelerating the heating process and if heating trends continue we could be heading to a 50% extinction of all plant and animal species on the earth. This is the first time global temperature trends have been compared to extinction rates for the entire fossil record, and the prognosis is not look so good. Of the five major mass-extinctions that have occurred in 350 million year span of the fossil record, four have occurred during greenhouse phases.

Whether or not mass exstinction is just scientific paranoia remains to be seen, however many species of plants and animals are already finding it increasingly hard to adapt to their changing habitats. The Polar Regions and the flora and fauna that inhabit them are especially in danger. If a mass extinction is unavoidable, then we are heading towards a reset of Earth’s animal hierarchy, and like mammals after the dinosaurs, a new species may inherit the earth. It would be interesting to hypothesise who the new dominant species might be; my vote is for the genetically modified mice.

Sources
http://www.york.ac.uk/admin/presspr/pressreleases/massextinctions.htm
http://www.livescience.com/strangenews/070808_GM_mass_extinctions.html

Can't Fight the Moonlight

Studies indicate the sunlight that is reflected off the moon’s surface may indeed be romantic! Following a full moon, mass spawning of corals in the barrier reef occurs due to the cryptochromes, or photoreceptors of plants that detect the blue light. This is what tells the coral that it is the right hour of the right few nights to spawn during the spring.

Cryptochromes are believed to be the predecessors of eyes and exist not only in coral, but also insects, humans, and other mammals. Linked with a system which repairs damage done by ultraviolet radiation, cryptochromes may have evolved in eyeless beings that were incompatible with sunlight.

Brain monitoring of night-migrating birds demonstrate increased usage of cryptochrome-expressing neurons as well as forebrain region, suggesting that cryptochrome receptors may also have a role in birds’ directions, providing night-migratory birds with a magnetic compass of sorts, dependant on blue light.

If cryptochromes are vital to a coral’s spawning and in the migration of birds, what are the effects of moonlight on our cryptochromes? Does a full moon really make us wild? If they are still in our DNA, do we still have a use for them?

There is no doubt that cryptochromes do have a function in the circadian rhythms of organisms, which regulate metabolism, physiology, and behavior. However, up to this point, studies on how moonlight or a full moon may affect human behavior are inconclusive.

From what I have heard from working professionals who deal with people- a nurse and a policeman, I suspect that it’s not just a superstition that a full moon has an effect on people. They didn’t say that people were more violent or aggressive (a theory is that more people will be assaulted during a full moon due to increased aggression), however they both agree that people do seem to get a little crazier and their late shifts get a little busier than normal. I think that the area of cryptochromes needs to be explored further; it’s really fascinating that the photoreceptors may have so many different functions.

http://www.scienceagogo.com/news/20070922011725data_trunc_sys.shtml
http://en.wikipedia.org/wiki/Cryptochrome#_note-2
http://www.flickr.com
http://www.plosone.org/article/fetchArticle.action?articleURI=info:doi/10.1371/journal.pone.0000937

A Bird's Eye View

Here is my brat Parrot: Piper. About six years ago after my childhood Budgie had died and I had returned home from traveling I decided I needed another bird. I had worked a fair bit and saved some money so that I would be able to get pretty much any parrot I wanted, however, having worked in a bird store (for a short time when I was in middle school) I chose wisely:

 

African Gray’s and Amazon’s are too noisy; Lorri’s need special food; Cockatoo’s are destructive. It’s quite a tough decision if you’ve been around the different breeds.

 

Choosing a bird is like choosing a dog that is going to live for 40-80 years. I eventually narrowed it down to two breeds, which would fit my lifestyle: the eclectus and the pionus.

 

Piper is a white- capped pionus. I chose him because of the breeds versatility. They don’t normally travel in flocks, they don’t eat a lot of fruit (some birds need a lot of fruit to stay healthy), they don’t chirp like those annoying cockatiels, and they tend to mate for life. Translation: he can be left home alone while I work, he won’t scream to communicate with the outside birds, and he will bond nicely with people.

 

One thing I wasn’t expecting was the amount of people who didn’t think he was a parrot because he didn’t have pretty colours. He’s green and blue with a peach bum. The peach colour is on his underside though and isn’t visible if he isn’t flying above you.

 

I found it weird that my parrot was boring so I researched him. It turns out that birds can see better than us humans. For starters, they can see ultraviolet light, whereas our eyes are sensitive to it and we loose our colour perception (when white glows and everything becomes purple).

Birds also have four dimensions of colour, which means everything that we see, they see in more vibrant hues. So a boring black crow to a bird is actually quite colourful and attractive.

 

Birds also use florescent colours to attract each other. That’s why some species have weird reflective markings: like a budgies cheek, a crows feather tips, or a ringneck’s, ring of colour around his neck. Take a good look at Piper again at the top of the page. Those multicolour feathers on the back of his head going down his neck are his reflective markings. They extend down his back and make him a pretty flamboyant bird when viewed by other birds, so he’s only a boring green/ blue hue to us.

 

Birds have many other advantages with their eyes and head. It is the most important part of their features for survival. The positioning of their eyes gives them a broader view than humans and they can also rotate their neck at least 180 degrees, sometimes more depending on the species. This allows them to see food or enemies and navigate when flying.

 

Ever wonder why pet birds rarely return home?

 The use of giant eyes have to be trained, it’s like returning vision to someone who was never able to see and then wondering why they can’t identify anything without touching it.  Birds need to learn how to navigate or they won’t know how. If a pet bird gets loose, unless he was taught how to find home again, he might not come back. You just have to hope he can’t fly far enough to get completely lost. This is why it’s good to let birds have a little bit of flight inside the house every now and again before you clip their wings (they learn to navigate how to land, and when they start getting obnoxious you clip them; some don’t need to be kept clipped it depends on behavior).

 

It’s sad that some birds are kept in cages. If they are looked after properly and trained they can learn to do everything a dog can do (fetch, rollover, speak). It takes time and patience but with a 40-80 year lifespan it just might be worth it.

 

On the angle of birds eyes:

http://birding.about.com/od/birdanatomy/a/birdsight.htm

 

On the colours that birds can see:

http://www.bio.bris.ac.uk/research/vision/4d.htm

 

 

Transformers of the Sea

We all know about how animals can camouflage themselves to hide themselves from predator and/or prey, but who has heard of an animal that will actually imitate other animals in their environment? Discovered in 1998, the Indonesian Mimic Octopus, Thaumoctopus mimicus has been found to impersonate several ocean dwellers. Preys to deep water carnivores, the Mimic Octopuses often take shape of more poisonous animals to deter these hunters; while on the opposite end of things, change shape to attract the prey that might normally be too quick for the octopi to catch. Like all octopi, the mimic octopus is very flexible and can contort itself well- well enough, in fact, to fool a crab into thinking it could be a possible mating partner. Shapes that the octopus has said to have been caught in include that of the sea snake, lionfish, flatfish, brittle star, giant crab, sea shell, stingray, jellyfish, sea anemone, and mantis shrimp.

These Octopi are found in the murky waters around the Indo-west Pacific Ocean and can grow up to two feet in length. They feed in many different ways. Firstly, it can catch prey with its arms and kill it with its beak. Second, it can suck up the insides of their prey after paralyzing them with a poison; third, it may dig into the holes of prey, taking up the food with its arms; and lastly, it can swirl small prey into its suckers, entrapping them. They are brown and white in color, but do have the ability to change in both color and texture. They have a large brain and great eyesight, but they are deaf.

The number of sea creatures that the octopus copycats is disputed somewhat as well as how they have come about this ability. Some think that over the years, only the good impersonator octopi have survived, leaving us the Mimic species; while other theories suggest that the mimicry is misinterpreted and is just part of their sexual selection.

After watching videos and seeing pictures, I can’t imagine how the imitations could not be done purposefully. I think the intelligence in the octopus is amazing. Imagine how much concentration it takes to dance and to be aware of where you are and how you are moving. This is what the mimic octopus can and must do (while swimming), and do a good enough job to fool predator and prey.
http://www.youtube.com/watch?v=knoAHiM7z_s

http://news.nationalgeographic.com/news/2001/09/0920_octopusmimic_2.html

http://en.wikipedia.org/wiki/Mimic_Octopus

http://www.flickr.com/

http://www.succeedsocially.com/coolanimals