Saturday, October 25, 2008

Photohunter: Scary fish

This is a fangtooth fish, a deep water fish with very large teeth. It's been said that they have the largest teeth to body size ratio of any fish. They are found around 2,000 feet, and can be found as deep as 5,000 feet.

These fish are the poster child of the deep sea fish and can be seen on any special featuring deep sea animals. Although they general do extreme close-ups of the face, which makes them seem very large and frightening, they only get 5 inches (13 cm) in length. They are the terror of various shrimps, small fish, and cephalopods, that make up the majority of their diet.

There are only two species of fangfish world-wide, one which is present world-wide, and the other which is only found off the pacific coast.

Wednesday, October 22, 2008

Life photo meme: Misunderstood animal

Which of these is a misunderstood animal?

Sharks have a undeserved reputation of vicious man-eaters, who'd bite your arm off as soon as look at you, and go through the sea eating everything in there path. However, I would bet that more people would agree with the statement that sharks are animals, then would agree with the statement that humans are animals. But in what kingdom would we be placed?
  • Plantae: Multi-cellular, non-motile, and autotrophic. We do move, and don't photosythesize so that leaves us out.
  • Fungi: Multi-cellular, non-motile, and heterotrophic. Again, no, because we move.
  • Protozoa: Generally unicellular, generally motile, can be heterotrophic or autotropic. While this is a grab-bag category, most are unicellular and live in an aquatic environment. That leaves us out.
  • Monera: Unicellular (but lacks many membrane-bound organelles), can be motile or non-motile, can be heterotrophic or autotropic. I don't think anybody would try to insist that we are bacteria (at least in the literal sense).
  • Animalia: Multicellular, motile, heterotrophic. Bingo! We do walk around, eat things, and we are multicellular.

That was a short list (just three characteristics), but you can see that the animal kingdom is where we fit. So for those of you who missed it, the complete classification of humans:

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Family: Hominidae
Genus: Homo
Species: sapiens

Note: the shark in the picture is my favorite shark, the zebra shark (Stegostoma fasciatum). They can grow 11 feet long, and eat crabs, clams, and fish they suck out of the sand. As an adult, they look like a potato with spots, and a very long tail.

Friday, October 17, 2008

Life photo meme: Bat star

Kingdom: Animalia

Phylum: Echinodermata

Class: Asteroidea

Order: Spinulosida

Family: Asterinidae

It's hard for me to think of anything more voracious than a sea star. I like to refer to them as the walking stomachs of the sea. If you open one up, you will see the digestive gland and little else. This particular sea star is a bat star (Asterina miniata), and it eats plants (like surf grass), animals (anything it can catch, dead or alive), and even the thinnest biofilms (bacterial, protozoan). It basically everts its stomach on anything organic and digests it. The thin tissue in the picture is the bat star's stomach.

Bat stars will fight each other whenever they come into contact. A battle consists of one star trying to put its arm on another. So both stars will rear an arm up and very slowly try to lay it on top, like a slow-motion thumb war (you remember that game, right?). It's rather amusing to watch, if you have the time.

Saturday, October 11, 2008

Photohunter: Lazy

This photohunter I thought I'd honor my cat, Rob Anybody McFeegle, or Robbie for short. He's not any lazier than any other cat in general, but when he sleeps he is just too funny.

Like most cats, he spends a good amount of time sleeping on things that I need... like my hand while I am typing, or the keyboard, or various papers I am referencing.

Unlike my other cats, he does not spend a lot of time curled up in a corner. He likes to sleep sprawled out in the middle of the floor. His favorite position is on his back with his paws spread out.

Of course it's a good day when he can combine sprawling on the floor and laying on stuff I am working on.

Friday, October 10, 2008

Life photo meme: Swell shark

Kingdom: Animalia

Phylum: Chordata

Class: Chondrichthyes

Order: Carcharhiniformes

Family: Scyliorhinidea

This is a swell shark, or Cephaloscyllium ventriosum. They are common inhabitants of the kelp forests; found during daylight hours laying about on the floor. Swell sharks have a neat trick of inflating by gulping down water or air. They can use this technique to wedge themselves into rocks, making it impossible for predators to get them out. There is a really awesome website describing all of the research done on them here. I am going to summarize some of it, but be sure to check it out for the full detail.

Swell sharks lay eggs, which can take up to a year to hatch. They are poor swimmers and nocturnal, but don't use light cues to initiate activity. Instead they relay on internal cues, general going for a 12 hours of sleep, 12 hours of activity. When they hunt, they use two different tactics: it waits until the fish is close to its head, than sucks it into its mouth with a "gulp", or it slowly opens its mouth and waits till a fish drifts in.

Saturday, October 4, 2008

Photohunter: Funny, but sad...

Signs like this always make me laugh and then shake my head. It's always sad that signs like this are needed. Sometimes people just need to use a little courtesy and common sense. What's really sad is that I know that even with the sign, there is a very good chance that stuff is still being tossed at the alligator.

Friday, October 3, 2008

Life photo meme: Mantis diversity

Desert mantis photographed by Los_Cat

Kingdom: Animalia

Phylum: Arthropoda

Class: Insecta

Order: Dictyoptera

Family: Mantidae

I thought I'd put up some pictures of wild mantises. There are some 2,000 species of mantis world wide. As they are often ambush predators, they come in a wide variety of shapes, sizes, and colors to match their preferred hunting grounds. Some of the mantises which hunt on flowers are truly amazing looking. These two mantises were photographed in different habitats, and you can definitely see the differences.

Mantises have pretty amazing eyesight. Their compound eyes have specialized regions with overlapping fields of view that allows them to track movement very well [1]. They have amazing flexibility in their necks, allowing them to rotate their heads. This head movement can also help them estimate distance to their prey [2]. Some species have an 'ear' on their thorax which allows them to detect bat calls [3].