Courtesy Chris PederickSensory organs dotting the heads of members of the crocodilian family show evidence of being more sensitive to touch than even human finger tips. Some of the literally thousands of minute pigmented bumps, called Integumentary sensory organs ( ISOs) covering the reptiles' tough, armored skin are used to detect surface ripples or water movement for determining prey location. But many of the remaining receptors can detect the slightest touch from potential prey, and cause a croc's or gator's jaws to snap shut with lightning speed. The study was done by researcher Duncan Leitch and biologist Kenneth Catania, and appears in the Journal of Experimental Biology.
Story at ScienceDaily.com.
Oh, Buzzketeers, the Fates smile on us today! They have sent a truly glorious monster for us to enjoy: a 21-foot-long, 2,370-pound saltwater crocodile!
The beast had been causing something of a ruckus in a southern Philippine town, having attacked and eaten a villager's water buffalo (and maybe a fisherman or two), so they captured it alive!
The croc will go to a planned ecotourism park in the area, where it will continue to be big and frightening.
Check out the link for photographs and video of the crocodile.
Crocodile tears have long been held to be the “holy grail” of animal cruelty advocates worldwide. Practically unique in the animal kingdom, open displays of crocodile emotion have traditionally eluded even the most ardent of professional animal abusers. Whereas fish cry constantly, and most mammals and birds can be made to at least tear up with a threatening glance, crocodiles present an altogether more complicated challenge.
It seems that the legend of crocodile tears began, among Westerners at least, in the 15th century, with the publication of the book “The Voyage and Travel of Sir John Mandeville,” which contained the passage, “In that country be a general plenty of crocodiles …These serpents slay men and they eat them weeping.”
Mandeville’s observations, however, have been nigh on impossible to replicate in the last six hundred years. While most animals succumb to weeping after a smack or two, the bony scutes embedded in crocodile skin make this sort of treatment a waste of time. Indeed, these scutes often allow crocodiles to survive gunshot wounds (scutes, or osteoderms, are what compose the armor of armadillos, as well as that of extinct animals, like anklyosaurs, or the SMM’s glyptodont).
Verbal abuse is no more effective than physical, with “You’re so fat” comments and “Yo mama” jokes barely appearing to even register with most crocodiles. Also, lacking any substantial sort of “psychology” crocodiles and their kin are essentially immune to psychological mistreatment.
Early in the last century, one scientist when so far as to rub onion and salt into a crocodile’s eyes*. While he may have had the beginnings of a mouth-watering recipe for crocodile eyeballs, the experiment yielded no tears, leaving many to believe that the notion of crocodile tears was a myth in the first place.
Not so, says University of Florida zoologist Kent Vliet. Vliet’s recent research seems to indicate that crocodiles do cry, but probably not for the reasons one might expect.
Part of the problem with looking for crocodile tears, as you can probably imagine, is distinguishing the tears from plain old water. With fish, which are emotionally unstable and weak-willed, it’s quite safe to assume that they are crying constantly, constantly surrounded by water as they are. Crocodiles are much more inscrutable.
What Vliet did was to videotape captive caimans and alligators (both close relatives to the crocodile) while they were feeding. These captive animals have been trained to eat on dry land, unlike wild crocodiles, which often feed while at least partially in the water. The tapes showed the crocodilians’ previously dry eyes not only crying, but also sometimes even “frothing and bubbling” as they ate.
There you have it. The precise reason for crocodile tears is still something of a mystery, though. Vliet believes that the tears may be the result of the huffing and hissing that generally accompanies crocodile feeding, with the air being pushed through the sinuses forcing tears from the lacrimal glands.
The main purpose of the crocodile’s lacrimal glands is the same as for our own – to lubricate the eyes. It’s possible that tear production during eating is to help lubricate food, as some of the tears would run through the sinuses and mix with saliva in the mouth. The tears might also help protect the eyes, which recede somewhat into the crocodile’s head as it manipulates its mouth. After all, "there's a lot of drama going on around the head while they are subduing prey," says Vliet.
So next time you’re being cruel to a crocodile, don’t feel bad if it isn’t crying; it’s not your fault. You just have to be more creative. Try feeding it a really disgusting meal, or giving it a little food and then taking it away – there’ll always be a satisfying way to bring a crocodile to tears, for those who are willing to try hard enough.
*This is apparently true – a scientists really did try rubbing onions and salt in a crocodile’s eyes to see if it would cry.
Lately I’ve been reading a book called “Predatory Dinosaurs of the World” by Gregory S. Paul that details the traits and behaviors of carnivorous dinosaurs throughout the Mesozoic Era. Of course, since most dinosaurs (except birds) have been extinct for 65 million years, the theories in the book derive mainly from clues left in the fossil record. However, a lot can also deduced from studying and comparing the behaviors of present day predators and prey. It’s easy to surmise that not much in that arena has really changed over time.
Which brings me to this amazing piece of video I stumbled upon on YouTube. It was taken at South Africa's Kruger National Park by tourist David Budzinski, and is a great example of predator-prey behavior! This one even has a couple surprises which I wasn't expecting. I think you’ll find it as fascinating as I did.