Monday, December 11, 2006

Groups Of Animals Kingdom

In this post I will be showing you different types of animals. There are different animals so there are groups of animal.
Deuterostomes differ from the other Bilateria, called protostomes, in several ways. In both cases there is a complete digestive tract. However, in protostomes the initial opening (the archenteron) develops into the mouth, and an anus forms separately. In deuterostomes this is reversed. In most protostomes cells simply fill in the interior of the gastrula to form the mesoderm, called schizocoelous development, but in deuterostomes it forms through invagination of the endoderm, called enterocoelic pouching.All this suggests the deuterostomes and protostomes are separate, monophyletic lineages. The main phyla of deuterostomes are the Echinodermata and Chordata. The former are radially symmetric and exclusively marine, such as sea stars, sea urchins, and sea cucumbers. The latter are dominated by the vertebrates, animals with backbones. These include fish, amphibians, reptiles, birds, and mammals.
In addition to these, the deuterostomes also include the Hemichordata or acorn worms. Although they are not especially prominent today, the important fossil graptolites may belong to this group. The Chaetognatha
or arrow worms may also be deuterostomes, but this is less certain

The Ecdysozoa are protostomes, named after the common trait of growth by moulting or ecdysis. The largest animal phylum belongs here, the Arthropoda, including insects, spiders, crabs, and their kin. All these organisms have a body divided into repeating segments, typically with paired appendages. Two smaller phyla, the Onychophora and Tardigrada, are close relatives of the arthropods and share these traits.
The ecdysozoans also include the Nematoda or roundworms, the second largest animal phylum. Roundworms are typically microscopic, and occur in nearly every environment where there is water. A number are important parasites. Smaller phyla related to them are the Nematomorpha or horsehair worms, which are invisible to the unaided eye, and the Kinorhyncha, Priapulida, and Loricifera. These groups have a reduced coelom, called a pseudocoelom.
The remaining two groups of protostomes are sometimes grouped together as the Spiralia, since in both embryos develop with spiral cleavage.

The Platyzoa include the phylum Platyhelminthes, the flatworms. These were originally considered some of the most primitive Bilateria, but it now appears they developed from more complex ancestors.
A number of parasites are included in this group, such as the flukes and tapeworms. Flatworms lack a coelom, as do their closest relatives, the microscopic Gastrotricha.
The other platyzoan phyla are microscopic and pseudocoelomate. The most prominent are the Rotifera or rotifers, which are common in aqueous environments. They also include the Acanthocephala or spiny-headed worms, the Gnathostomulida, Micrognathozoa, and possibly the Cycliophora. These groups share the presence of complex jaws, from which they are called
the Gnathifera.

The Lophotrochozoa include two of the most successful animal phyla, the Mollusca and Annelida. The former includes animals such as snails, clams, and squids, and the latter comprises the segmented worms, such as earthworms and leeches. These two groups have long been considered close relatives because of the common presence of trochophore larvae, but the annelids were considered closer to the arthropods, because they are both segmented. Now this is generally considered convergent evolution, owing to many morphological and genetic differences between the two phyla.
The Lophotrochozoa also include the Nemertea or ribbon worms, the Sipuncula, and several phyla that have a fan of cilia around the mouth, called a lophophore. These were traditionally grouped together as the lophophorates, but it now appears they are paraphyletic, some closer to the Nemertea and some to the Mollusca and Annelida. They include the Brachiopoda or lamp shells, which are prominent in the fossil record, the Entoprocta, the Phoronida, and possibly the Bryozoa or moss animals.

Thursday, December 07, 2006

Animal Hunting

Hunting is the practice of pursuing animals to kill them for food, recreation, or trade of their products. In modern use, the term refers to regulated and legal hunting, as distinguished from poaching, which is the killing, trapping or capture of animals contrary to law. Hunted animals are referred to as game animals, and are usually large mammals or migratory birds.
By definition, hunting strictly speaking excludes the killing -though the same techniques may be used- of individual animals that have become dangerous to humans and the killing of non-game animals, domestic animals, or vermin (or "varmints") as a means of pest control. Hunting may be a component of moder, wildlife management, sometimes used to help maintain a population of healthy animals within an environment's ecological carrying capacity. Wildlife managers are frequently part of hunting regulatory and licensing bodies, where they help to set rules on the number, manner and conditions in which game may be hunted or "harvested."

This is not fair because why is it fair that animals get killed for fun,if it is for searching for food then i do not mind. But i am talking about people killing animals for fun. Imagine if you were an animal and you got killed for fun it's not fair.

Monday, November 27, 2006

Greenhouse Gases

Greenhouse gases (GHGs) are gaseous components of the atmosphere that contribute to the "greenhouse effect". Although uncertainty exists about exactly how earth's climate responds to these gases, global temperatures are rising. Some greenhouse gases occur naturally in the atmosphere, while others result from human activities. Naturally occurring greenhouse gases include water vapor, carbon dioxide, methane, nitrous oxide, and ozone. Certain human activities, however, add to the levels of most of these naturally occurring gases.

When sunlight reaches the Earth's surface, some is absorbed and warms the earth. Because the earth is much cooler than the sun, it radiates energy at much longer wavelengths than the sun (see Black body radiation and When's displacement law); some of these longer wavelengths are absorbed by greenhouse gases in the atmosphere before they are lost to space. The absorption of this longwave radiant energy warms the atmosphere (the atmosphere also is warmed by transfer of sensible and latent heat from the surface). Greenhouse gases also emit longwave radiation both upward to space and downward to the surface. The downward part of this longwave radiation emitted by the atmosphere is the "greenhouse effect." The term is in fact a misnomer, as this process is not the primary mechanism that warms greenhouses.
The major natural greenhouse gases are water vapor, which causes about 36-70% of the greenhouse effect on Earth (not including clouds); carbon dioxide, which causes 9-26%; methane which causes 4-9%, and ozone, which causes 3-7%. Note that it is not really possible to assert that a certain gas causes a certain percentage of the greenhouse effect, because the influences of the various gases are not additive. (The higher ends of the ranges quoted are for the gas alone; the lower ends, for the gas counting overlaps.)

Friday, November 24, 2006

Animal Rights

Animal rights, animal liberation, or animal personhood, is the movement to protect non human animals from being used or regarded as property by humans. It is a radical social movement [4] insofar as it aims not only to attain more humane treatment for animals, which is the sole focus of animal welfare, but also to include species other than human beings within the moral community by giving their basic interests — for example, the interest in avoiding suffering — the same consideration as those of human beings. The claim is that animals should no longer be regarded legally or morally as property, or treated as resources for human purposes, but should instead be regarded as persons.
Animal law courses are now taught in 69 out of 180 United States law schools, and the idea of extending personhood to animals has the support of some senior legal scholars, including Alan Dershowitz and Laurence Tribe of Harvard Law School.The Seattle-based Great Ape Project is campaigning for the United Nations to adopt a Declaration on Great Apes, which would see gorillas, orangutans, chimpanzees and bonobos included in a "community of equals" with human beings, extending to them the protection of three basic interests: the right to life, the protection of individual liberty, and the prohibition of torture. This is seen by an increasing number of animal rights lawyers as a first step toward granting rights to other animals.

every animal has a reason to live. so people have no right to harm them (this means plan
ts as well).

Ozone Layer

The ozone layer, or ozonosphere layer (rarely used term), is the part of the Earth's atmosphere which contains relatively high concentrations of ozone (O3). "Relatively high" means a few parts per million - much higher than the concentrations in the lower atmosphere but still small compared to the main components of the atmosphere. The ozone layer was discovered in 1913 by the French physicists Charles Fabry and Henri Buisson. Its properties were explored in detail by the British meteorologist G. M. B. Dobson, who developed a simple spectrophotometer that could be used to measure stratospheric ozone from the ground. Between 1928 and 1958 Dobson established a worldwide network of ozone monitoring stations which continues to operate today. The "Dobson unit", a convenient measure of the total amount of ozone in a column overhead, is named in his honor.

The photochemical mechanisms that give rise to the ozone layer were worked out by the British physicist Sidney Chapman in 1930. Ozone in the earth's stratosphere is created by ultraviolet light striking oxygen molecules containing two oxygen atoms (O2), splitting them into individual oxygen atoms (atomic oxygen); the atomic oxygen then combines with unbroken O2 to create ozone, O3. The ozone molecule is also unstable (although, in the stratosphere, long-lived) and when ultraviolet light hits ozone it splits into a molecule of O2 and an atom of atomic oxygen, a continuing process called the ozone-oxygen cycle, thus creating an ozone layer in the stratosphere ,the region from about 10 to 50 km (32,000 to 164,000 feet) above Earth's surface. About 90% of the ozone in our atmosphere is contained in the stratosphere. Ozone concentrations are greatest between about 15 and 40 km, where they range from about 2 to 8 parts per million. If all of the ozone were compressed to the pressure of the air at sea level, it would be only a few millimeters thick.
Ten percent of the ozone in the atmosphere is contained in the troposphere, the lowest part of our atmosphere where all of our weather takes place. Tropospheric ozone as two sources: about 10 % is transported down from the stratosphere while the remainder is created in situ in smaller amounts through different mechanisms.

Tuesday, November 07, 2006

Endangered Species

In physics, a magnetic field is that part of the electromagnetic field that exerts a force on a moving charge. A magnetic field can be caused either by another moving charge (i.e., by an electric current) or by a changing electric field. The magnetic field is a vector quantity, and has SI units of tesla, 1 T= 1 kg·s−1·C−1.
There are two quantities that physicists may refer to as the magnetic field, notated H and B. In a vacuum, they are equal. Although the term "magnetic field" was historically reserved for H, with B being termed the "magnetic induction," B is now understood to be the more fundamental entity, and most modern writers refer to B as the magnetic field, except when context fails to make it clear whether the quantity being discussed is H or B

The cause of nuclear power has effected the animals ,for example whales and dolphines also many species of fish are getting stranded in the beach.To prevent this from happening we should tend to use wing,solar,hydroelectric energy more often.