Animal Life

How do spiders spin their webs?

Masterfully.

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. Read more…

What do snakes eat?

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.

What is the world’s smallest mammal?

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.

What is the world’s oldest dog?

While reliable information on this question is fairly hard to come by, there have been a few reliably substantiated cases of dogs living for almost 30 years.

The oldest dog that has been somewhat reliably documented was an Australian cattle-dog named Bluey. He is reported to have lived from June 7, 1910 to November 14, 1939 (29 years, 5 months and 7 days). Bluey was owned by Les and Esma Hall of Rochester, Victoria, Australia.

In September, 2008 another dog was reported to have died at over 29 years old. Bella, a Labrador mix was owned by David Richardson of Derbyshire, England. The Guinness Book of World Records reports the oldest dog (with reliable documentation) to be Butch, a 28-year old Beagle in America who died in 2003.  See the list of oldest dogs on record.

Bramble, the Labrador pictured above was reliably recorded to have lived over 27 years and died in Somerset, England in 2003. He currently has the position as the second oldest dog on record.

Sources: The World’s Oldest Dog Dies and Vegetable-Eating Dog Lives to Ripe Old Age of 27.

Why do nine-banded armadillos always have four offspring of the same gender?

The Dasypus novemcinctus, or nine-banded armadillo female almost always gives birth to four young of the same sex. The offspring are actually quadruplets that come from one fertilized egg splitting into four parts.

The general wikipedia description follows: the Nine-banded Long-nosed Armadillo or just Nine-banded Armadillo, (also known as the poor man’s pig or poverty pig), is a species of armadillo from North, Central and South America. It is the most widespread member of the group. Its ancestors evolved in South America, but were able to invade North America during the Great American Interchange after the Isthmus of Panama formed 3 million years ago.

The Nine-banded Long-nosed Armadillo is a solitary, mainly nocturnal animal, found in many kinds of habitats, from mature and secondary rainforests to grassland and dry scrub. It is an insectivorous animal, feeding chiefly on ants, termites and other small invertebrates. This species is the only known animal that is able to inflate its own intestine in order to float across a river. It can also hold its breath for up to 6 minutes in order to walk across the bottom of narrow rivers. Additionally, the nine-banded armadillo always produces four identical offspring. The armadillo can jump three to four feet (90-120 cm) straight in the air if sufficiently frightened, making it a particular danger on roads.

What is the largest spider in the world?

The largest spider in the world is a tarantula called the Goliath Birdeater. An adult can weigh over four ounces (about the size of a large mouse) and has a leg span of up to 12 inches. The spider was given its unique name by Victorian explorers who witnessed one eating a hummingbird although birds are not typically part of its diet. They survive mostly on small insects and meal worms but will occasionally eat small rodents such as mice, shrews and moles.

Wild goliath birdeaters are a deep burrowing species, found commonly in marshy or swampy areas. Goliath birdeaters usually live in burrows in the ground that they have either dug themselves or have been previously abandoned by rodents or other similar creatures.

The goliath birdeater is fairly harmless to humans, as are most species of tarantulas. Like all tarantulas, it has fangs large enough to break the skin of a human and they do carry venom in their fangs and have been known to bite humans when threatened, but the venom is relatively harmless and its effects are comparable to those of a wasp’s sting. Tarantulas generally bite humans only in self-defense, and these bites do not always result in envenomation. The goliath birdeater has poor eyesight and mainly relies on vibrations in the ground that they can sense from their burrows.

Source: Wikipedia.

What is the most venomous animal?

First, we should address the difference between venomous and poisonous. Most poisonous animals have toxins on or in their skin. They may secrete toxins that would be deadly to the touch – for either humans or other animals. So for poisonous animals, many scientists agree that the poison dart frog and some salamanders are the most poisonous. As little as two micrograms of toxin from the poison dart frog could kill a human.

A venomous animal also has toxins, but is typically delivered by biting, stinging or stabbing. While this is sometimes debated, the box jellyfish is often considered the world’s most venomous animal. You may have heard of the inland taipan of Australia as being very venomous, and it is. It is considered the most venomous land snake in the world.

Sources: Wikipedia and the discoverymagazine.com Dear Digger Doug Q&A.