You might think the animal with the longest gestation period would be one of the larger mammals, but in fact it is the Alpine black salamander. It is a viviparous amphibian which lives in the high altitude Swiss Alps. At altitudes above 4,600 feet, it’s gestation period can be up to 38 months. It bears two fully metamorphosed young.

Like the rings on the cross section of a tree, fish scales also have rings. Fish scales have concentric ridges called circuli which reflect the growth patterns of the fist and can be used to estimate the age. From “The Handy Science Answer Book,” the portion of the scale that is embedded in the skin contains clusters of these circuli, called annuli. Each of these clusters mark one year of growth.

So what about fish that don’t have scales? Like catfish, dolphins or sharks? I’ve heard that a seasoned biologist (or ichthyologist) could possibly make a fair estimate by looking at their teeth. But I would take this answer with some skepticism and say that this is probably difficult to do.

Source: http://mindjourney1962.wordpress.com

There are a couple of ways this question can be answered. Sea anemones and sponges are animals and they hardly move at all, so I guess one of these guys could be considered very slow indeed. Clams, oysters and snails are pretty slow as well. But I guess most people asking this question are actually wondering what are the slowest vertebrates.

The winner in this category is most likely the three-toed sloth. It has been said that it would take a sloth about a month to walk a mile, though this is still a bit unfair since sloths really don’t ever walk. They spend their time hanging upside down in trees. They even sleep, eat and have babies while hanging upside down. I imagine they even do what they do to make babies while hanging upside down, but I’ve never personally witnessed sloth copulation. Probably a good thing.

Inland taipans are also called fierce snakes and can grow up to 10 feet (2.7 meters) although half of that is the norm. This snake changes color according to season. They range from dark brown to straw colored during the year but at winter they go darker and in the summer they go lighter.

Taipans hunt mammals so their poison can knock out warm-blooded, fuzzy rodents and animals, including humans. In a single strike (one bite) the venom can quickly paralyze a small animal or wipe out several adult humans. As the poison spreads, the victim will encounter headaches, nausea, vomiting and stomach pains. Sometimes there are convulsions and in extreme cases, coma.

If that’s not bad enough, the poison eats away at muscle tissue. Urine from the victim turns reddish-brown as their muscles deteriorate and pass through the kidneys. Internal bleeding is a major problem from taipan bites. The poison also prevents blood from clotting so the bite continues to bleed. This can cause internal hemorrhaging, especially in the brain. All this sucks for the bite victim but it’s great for the snake who only has to wait for its prey to stop convulsing before enjoying dinner. Taipans rarely attack humans, except in self-defense, so as long as they are left alone, humans will be too.

Source: Kidzworld.com.

A more scientific method is through close observation and comparing your tadpole to a known chart. The below images and chart should help you get started.

First, where are the eyes? Are they lateral or dorsal?

Next, check the vent location. You may have to hold the tadpole in your hand to check this. Is it Medial or Dextral?

Next you’ll need to check the tail musculature. Is it high, medium or low?

And lastly, you’ll compare these results with the tadpole anatomy wheel below. (Click on the picture to see a full-size image.)

Following this procedure should give you a good idea and help you narrow it down. Of course, the only surefire way to identify the species will be to wait and see what kind of frog it grows into. The source of these images is the Tutorial on Tadpole Morphology from the U.S. Geological Survey (USGS).

A dog’s retina has a much higher proportion of rods than cones than the human retina. This is why we can see more details at a longer distance than our dogs, but they can see better than we can in low light conditions. One estimate is that a dog can see at about 25 yards what we can see at 75 yards. If this is the case, we could call a dog’s vision 20/75 on the standard 20/20 scale. Of course these are estimates as it would be pretty difficult to get a dog to read an eye chart at any distance.

So why did the dog’s and man’s retinas evolve this way? Most likely because it was more advantageous for the dog to be able to see in low light conditions. The nearest wild relative to the dog is the wolf, which often hunts near the hours around dawn and dusk. Many predators hunker down during the middle of the day and thus don’t need to have the best vision in this time. Man evolved from any nocturnal habits such as these millions of years ago and has likewise benefited from having better daytime vision- ie., we have evolved to have more cones than rods.

Source: Wikipedia’s entry on dogs, eyesight.

The article goes on to say that you are more likely to get a serious illness from kissing another person than kissing a dog. A Yahoo! article claims the myth may have stemmed from the way dogs lick their wounds. This may have led to the belief that a dog’s saliva is healthy. This just isn’t the case. Nevertheless, you shouldn’t be afraid of a dog licking you. It may be gross, but it’s not very dangerous.

To spin a tale about the spider, member of the species arachnid, we must first examine the common thread that ties them together…the way they produce the silk they use to weave their webs, as well as other contraptions, to suit their particular needs.

Spiders differ from insects in that they have eight legs, eight eyes, in most cases, no wings, and have only two parts to their bodies, one of which produces silk. They are found in a host of climates, can scurry across the ground, can scale plants, and can skate on, and live in, water. These factors determine how the spider uses it’s silk, and what type of silk it produces.

Production of silk begins in certain glands located in the abdomen, or belly, of the beast. Spinning organs at the tip of the abdomen, contain many tiny holes, and function much as a sieve, through which the silk is pressed. The silk strained through is in liquid form, but immediately takes on a solid form, much like cotton candy does, when exposed to air.

The spider creates a variety of types of silk, each of which serves a separate, yet distinct function. Spiders use the sticky kind to spin webs, to catch and to hold the insects they invite into their parlors until they are ready for dinner. They use the non-sticky, stronger variety to tether down the spokes of the wheel, and yet a different kind of silk for their cocoons.

Even the webs the spider spins differ greatly, depending upon the factors listed above. The most common of all webs we see is the wheel-shaped web. Less common are the so-called “sheet” webs, which blanket surfaces with a funnel, or dome like shape. The trap-door spiders burrow out their webs, and complete them with built-in chutes, through which their unsuspecting guests fall through, right onto the spider’s plate. The web we see least often, is the air-tight, bell-shaped home some spiders build…probably because it is completely submerged in water!

Why aren’t spiders caught in their own webs?

In short, startled spiders can be entangled in their own webs, in the same manner as their prey. Generally speaking, however, the spider avoids this deadly mishap, by differentiating between the various types of silk it produces, and by knowing its home turf.

When the spider weaves its sticky, insect-catching type of web, it builds into it safety threads of the non-sticky variety, upon which it traverses without being snared. Its nimble, highly sensitive feet orient the spider about its new home, and past the potential pitfalls, to which its prey fall victim. Unless, of course, something, or someone, startles the spider, in which case all bets are off, and the parlor game is over.

Source: coolquiz.com.

This is a very generic question, but one that actually gets asked quite frequently.  Of course, the short answer is that snakes have a varied diet, depending on factors such as their species, size, age, geographic locale, etc. A fairly accurate answer for what most snakes eat might be: insects, worms, lizards, birds, small amphibians such as frogs and salamanders, and small mammals such as rats, mice and voles. But even this answer could vary depending on a location. A common garter snake that lives in a wooded area near a pond will likely eat more frogs than the garter snake found in your backyard which might live entirely on insects and the occasional mouse.

The more interesting answer is to the question: what do some of the larger more exotic snakes eat? Some snakes primarily eat other snakes (the bandy-bandy of Australia). Some snakes eat mostly the eggs of other animals (see image above). And some of the larger snakes such as pythons and other constrictors will eat small mammals when young and begin to eat larger animals such as pigs, monkeys and deer as they mature.

There has been some debate on this, depending on how you define an animal’s size. The Bumblebee Bat (Craseonycteris thonglongyai) is definitely the world’s smallest species of bat. It is about 30mm in length and weighs about 2 grams (less than an American penny). It is the only known species in its genus and is found in a tiny region of western Thailand, in the Sai Yok National Park, Kanchanaburi Province.

One of the more interesting notes is that the Bumblebee Bat was virtually unknown until 1974 when it was discovered by Kitti Thonglongya, a biologist in Thailand. Their habitat has been highly affected by deforestation and unsustainable levels of teak logging. In 1982, the Royal Forest Department of the Thailand Government only found 160 of them living in 3 caves, despite extensive surveys. Bumblebee bats are now considered one of the twelve most endangered species on the planet.

The other mammal in competition for the title of the “world’s smallest” is the Etruscan Pygmy Shrew (Suncus etruscus). This shrew weighs less than the Bumblebee Bat but the bat’s skull is shorter. [Wikipedia] The smallest mature specimens of this shrew are thought to weigh about 1.3 grams and measure 36 mm long. This small mammal is 60 mm from the tip of the nose to the base of the tail. This shrew has a lifespan of about 15 months and lives the forests and brush areas between Southern Asia and Southern Europe.

Sources: Portland State University,  Experience Festival.