Jeff LeClere, a herpetologist with the Minnesota Department of
Natural Resources, holds an American racer snake Wednesday
morning his team trapped and tagged. Alex Kolyer | MPR news
Saturday, August 30, 2014
Monday, August 25, 2014
A dyrosaurid, a marine crocodilian, swimming in the warm
surface waters during the end of the Cretaceous period. Illustration
credit: Guillaume Suan.
Saturday, August 23, 2014
Kucharzewski, C, et al. 2014. A taxonomic mystery for more than 150 years: Identity, systematic position and Malagasy origin of the snake Elapotinus picteti Jan, 1862, and synonymy of Exallodontophis Cadle, 1999 (Serpentes: Lamprophiidae). Zootaxa 3852.2 (2014): 179-202.
Tuesday, August 19, 2014
|Ninia atrata left, Nina franciscoi sp. n. right. T. Angarita-Sierra|
|Nina franciscoi sp n.,top, Nina atrata bottom.|
As for those undescribed Trinidad and Tobago squamates - one of them is a third species of Ninia. Below is typical Ninia atrata.
An adult Giant South American river turtle. The turtle
is the largest member of the side-necked turtle family and
grows up to nearly three feet in length. Photo credit: C.
Ferrara/Wildlife Conservation Society
Thursday, August 14, 2014
Wednesday, August 13, 2014
Geckos' feet are nonsticky by default, but they can activate
"stickiness" through application of a small shear force.
Photo credit: Image by Bjørn Christian Tørrissen,
In the Journal of Applied Physics, from AIP Publishing, Oregon State University (OSU) researchers describe their work exploring the subtleties of geckos’ adhesion system mechanism.
“Since the time of the ancient Greeks, people have wondered how geckos are able to stick to walls – even Archimedes is known to have pondered this problem,” said Alex Greaney, co-author and an assistant professor of engineering at OSU. “It was only very recently, in 2000, that Kellar Autumn and colleagues proved unequivocally that geckos stick using van der Waals forces.”
Van der Waals forces are weak atomistic level forces, “but geckos are able to take advantage of them because of a remarkable system of branched hairs called ‘seta’ on their toes,” Greaney explained. “These seta and their hierarchy can deform to make intimate contact with even very rough surfaces – resulting in millions of contact points that each are able to carry a small load.”
Geckos – as well as spiders and insects – have independently evolved the same adhesion system mechanism and have been using it for millions of years.
“Understanding the subtleties of the process for switching stickiness on and off is groundbreaking,” said Greaney. “By using mathematical modeling, we’ve found a simple, but ingenious, mechanism allows the gecko to switch back and forth between being sticky or not. Geckos’ feet are by default nonsticky, and this stickiness is activated through application of a small shear force. Gecko adhesion can be thought of as the opposite of friction.”
Greaney and colleagues also found that the entire process is quite subtle, so a synergistic combination of angle, flexibility, and extensibility of the hairs exists that results in incredibly robust and tough adhesion – but still allow geckos to unstick without expending energy.
So, what kinds of applications will these findings enable? For the past 10 years, many researchers have been trying to create ‘synthetic dry-adhesives’ to replicate the gecko. In fact, these types of adhesives are already being used in climbing robots that can search through earthquake rubble in search of survivors.
One application of the team’s work will be put to use improving these synthetic adhesives. “While we don’t envision Mission Impossible sticky gloves, which are inspired by or based on the concept of gecko adhesion, we envision that robots will use gecko adhesion in extreme environments in the future,” Greaney said.
What’s next? “One of the really cool things that we’ve found is the way seta can absorb a large amount of energy, but also can recover it,” Greaney said. “Absorbing energy makes for a tough adhesive joint – for the gecko, it means it can catch itself after jumping or falling and also enables a gecko to rapidly dart off in different directions to avoid predation.”
It’s surprising that the easy detachment mechanism can recover this stored energy, so the researchers are interested in studying whether this is coupled with other aspects of the gecko’s physiology to enable it to take advantage of the recovered energy – much like a kangaroo does when bounding. “We’re also interested in exploring how this robust, but switchable behavior, has the collective behavior of seta in a hierarchical system,” Greaney added.
Thursday, August 7, 2014
|Hatching Coastal Taipans. Photo credit: Luke Allen|
Tuesday, August 5, 2014
Sorry that it has been such a long time since I've written all you little people in my life. What with being president of the Tucson Herp Society, running a machine shop, and carrying the full brunt of organizing a radio telemetry study, I don't even have time to pick my nose any more. You want to see? Take a peek up either nostril. Nothin' but nose hairs with crusty booger stalactites clinging to them. A veritable hairy booger garden.
First off, the news is that John Slone found a snake on our plot. Don't bother congratulating him, as he as full of himself as he can be of late. If he were any more modest about it all, he'd be insufferable. Marty Feldner was with him when this snake was found. This made Marty an accessory to John's find, and he also has bit of afterglow going on about it all. When they handed me the bag, they also handed me an excuse as to why they didn't finish their side of the plot. They ran into what they called "an interloper." The snake in the bag was the interloper, and indeed, when a snake is captured in the proper fashion in the framework of the Suizo Mountain Project, it becomes an interloper. It's hard to write up old friends when new friends keep interloping.
John and Marty also possess some psychic prowess. As further explanation tumbled forth from their gullets about the interloper in the bag, they went on to
say it was a black-tailed rattlesnake, it was a female, and it was quite pregnant. Much later, the following morning, as I prepared, sanitized, and quarantined
the container, I realized how much their interloper intertwined with my life. However, as soon as our new molossus was dumped out of bag and into its sterile environs, I also grew psychic. It was indeed a molossus, it was indeed a female, and it was so pregnant that a gentle squeeze to the flanks would certainly jettison piles of baby rattlesnakes and the accompanying ooze that encapsulates them.
The first thought was "get a transmitter in her and get her back in the game." This was my big chance to actually nail some wild birthing behavior on the part of molossus. With this in mind, a drive to a favored DVM in Tempe transpired. The good Dr. DeNardo took one look at that snake and said "NO WAY." The normally fearless vet saw the hopelessness of the situation. There was no choice but to let nature take its course--at my house.
On 25 July, between the hours of 0700 and 1800, our girl dropped eight kids. Typing boy got excited, and started shooting images like a Colorado schoolboy.
But the newspaper background left something to be desired. Typing boy next bagged all the snakes, and filled the container with a substance best described as dusty yard dirt. The ambiance of this all natural enclosure required a hide box, and a convenient black plastic box swiped from Gordon Schuett was selected in order to assure that any photographs were doomed to fail. A whirlwind of photography then ensued, the results of which were highlighted when the little neonates crawled through the water dish and left dust streaks all over the enclosure. Tying boy then got wise, removed all the snakes from the container again, put my long-suffering wife Dianna to work making a sturdy cardboard hide box, and then pet store gravel and genuine Suizo rocks were added. (Some choice language was directed at my "can't-leave-a-snake-on-the-ground-companions" during this process).
The positive evolution of the container will be noted in the images that follow, but I'm sure that any photographers in this group (all of you!) will note that there is still room for improvement. This improvement will transpire as soon as these little bastards all shed. Then, we'll bag everybody up again, sterilize the container again, further cussing at Slone and Feldner will transpire, prickly pear cactus will be chopped off my yard plants, the nearest Neotomamidden will be picked clean, and some GENUINE nature faking will transpire.
It's time to go to images.
Image 1: Godzilla in situ. I wonder how Slone and Feldner knew she was pregnant?
And how did Godzilla get her name?
Image 2: Note the ventral scales on this snake. Kind of looks like Godzilla is trying to break out, doesn't it?
All the rest: Have a little mercy on the photographer. It would sure be nice if these neonatess were pretty. They aren't. They are ugly little olive drab turds. They fell out of the ugly tree and hit every branch on the way down. Never-the-less, they ARE molossus. And I may never get another opportunity like this again. We can hope that when these little bastards finally shed, they look nicer for the final shoot. Nature faking is best when the snakes are pretty.
Monday, August 4, 2014
This is a tree downed by logging in Madagascar. Photo credit:
Pseudophilautus poppiae, a microendemic shrub frog from
Southern Sri Lanka that only occurs in a few hectares of
cloud forest. Photo credit: Alex Pyron