ANIMALS
Animals are multicultural, Eukaryota organisms of the kingdom Animal also called Metazoa. All animals are motile, meaning they can move spontaneously and independently at some point in their lives. Their body plan eventually become fixed as they develop, although some undergo a process of metamorphosis later on in their lives. All animals are tropospheres: they must ingest other organisms or their products for sustenance.
Most know animals phyla appeared in the fossil record as marine species during the Cambrian explosion, about 500 million years ago. Animals can be divided broadly into vertebrates and invertebrates. Vertebrates have a backbone or spine vertebral column, and amount to less than five percent of all described animal species.
History of classification
Aristotle divided the living world between animals and plants, and this was followed by carl linnaeus, in the first hierarchical classification. In Linnaeus's original scheme, the animals were one of the three kingdoms, divided into the classes of Vermes, Insect, Pisces, Amphibian Aves. And Mammalia. Since then the last four have all been subsumed into a single phylum, the Chordata, where as the various other forms have been separated out .
Structure
With a few exceptions, most notably the sponges phylum Porifera and Placoza, animals have bodies differentiated into separate tissues. These include muscles, which are able to contract and control locomotion, and nerve tissues, which send and process signals. Typically, there is also an internal digestive chamber, with one or two opening. Animals with this sort of organization are called metastasize, or eumetazoans when the former is used for animals in general. All animals have Eukaryota cells, surrounded by a characteristic extracelluar matrix composed of collagen and elastic glycorproteins.This may be calciffied to form structures like shells, bones, and spicules. During development, It form a relatively flexible framework upon which cells can move aobut.
Reproduction and development
Nearly all animals undergo some form of sexual reproduction. They produce haploid gametes by meiosis see origin and function of the meiosis. The smaller, motile gametes are spermatozoa and the larger, non motile gametes are ova. These fuse to form zygote which develop into new individuals
Many animals are also capable of a sexual reproduction. This may take place through parthenogenesis, where fertile eggs are produced without mating, budding, or frag mention.
A zygote initially develops into a hollow sphere, called a blastula, which undergoes rearrangement and differentiation.
Cracking the Case
Like several murder mysteries, Hoogland’s study began with a body drop in an exceedingly quiet landscape: the scrublands of western Colorado’s Arapaho National life Refuge.
“For four months once a year, we have a tendency to live like grassland dogs,” says Hoogland, a National Geographic recipient. “We get to the colony early within the morning before the grassland dogs come to life, we have a tendency to sit in towers all day observation what they are doing, and that we keep till the last gnawer submerges, simply around sunset.”
During his 2007 field season, Hoogland noticed a white-tailed gnawer agitated around a young gnawing animal. Initially, he suspected that it had been killing another grassland dog’s pup, that isn't surprising: Infanticide is common in alternative gnawer species, although it's ne'er been determined in white-tailed grassland dogs.
Most know animals phyla appeared in the fossil record as marine species during the Cambrian explosion, about 500 million years ago. Animals can be divided broadly into vertebrates and invertebrates. Vertebrates have a backbone or spine vertebral column, and amount to less than five percent of all described animal species.
History of classification
Aristotle divided the living world between animals and plants, and this was followed by carl linnaeus, in the first hierarchical classification. In Linnaeus's original scheme, the animals were one of the three kingdoms, divided into the classes of Vermes, Insect, Pisces, Amphibian Aves. And Mammalia. Since then the last four have all been subsumed into a single phylum, the Chordata, where as the various other forms have been separated out .
Structure
With a few exceptions, most notably the sponges phylum Porifera and Placoza, animals have bodies differentiated into separate tissues. These include muscles, which are able to contract and control locomotion, and nerve tissues, which send and process signals. Typically, there is also an internal digestive chamber, with one or two opening. Animals with this sort of organization are called metastasize, or eumetazoans when the former is used for animals in general. All animals have Eukaryota cells, surrounded by a characteristic extracelluar matrix composed of collagen and elastic glycorproteins.This may be calciffied to form structures like shells, bones, and spicules. During development, It form a relatively flexible framework upon which cells can move aobut.
Reproduction and development
Nearly all animals undergo some form of sexual reproduction. They produce haploid gametes by meiosis see origin and function of the meiosis. The smaller, motile gametes are spermatozoa and the larger, non motile gametes are ova. These fuse to form zygote which develop into new individuals
Many animals are also capable of a sexual reproduction. This may take place through parthenogenesis, where fertile eggs are produced without mating, budding, or frag mention.
A zygote initially develops into a hollow sphere, called a blastula, which undergoes rearrangement and differentiation.
Cracking the Case
Like several murder mysteries, Hoogland’s study began with a body drop in an exceedingly quiet landscape: the scrublands of western Colorado’s Arapaho National life Refuge.
“For four months once a year, we have a tendency to live like grassland dogs,” says Hoogland, a National Geographic recipient. “We get to the colony early within the morning before the grassland dogs come to life, we have a tendency to sit in towers all day observation what they are doing, and that we keep till the last gnawer submerges, simply around sunset.”
During his 2007 field season, Hoogland noticed a white-tailed gnawer agitated around a young gnawing animal. Initially, he suspected that it had been killing another grassland dog’s pup, that isn't surprising: Infanticide is common in alternative gnawer species, although it's ne'er been determined in white-tailed grassland dogs.
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