Turtle
Do you think turtles and soft-shell turtles are the same animal? Don't be ridiculous, this is actually a difficult question to answer. If you think tortoises and turtles are the same animal, then in biological classification, tortoises and turtles are the same animal.
1. Boundaries of living things
The living things living on the earth There are about 200 species, but many new species are discovered every year, and it is estimated that the total number of organisms can reach more than 2,000 species. For such a large group of organisms, they must be classified into categories and systematically organized. This is the task of taxonomy.
2. Basic concepts of animal classification
1. Natural classification Method
Use a scientific method to determine the systematic position of animals in the animal kingdom from the similarity and relatedness in morphology, psychology, genetics, evolution, etc. This classification method can reflect the kinship relationship between each other and the experience of racial origin. It basically reflects the natural kinship relationship in the animal kingdom, so it is called natural classification method.
2. Classification level
In animal taxonomy, according to the differences between species or groups The different levels of common characteristics are mainly divided into several levels: "phylum, class, order, family, genus, species" to distinguish their ranking sequence. The species is the basic unit. Occasionally, subphylum, subclass, suborder, subfamily, subgenus, etc. are added for convenience, and below species there are subspecies, variants, variants, etc.
Kingdom: In more than 300 BC, Aristotle of ancient Greece divided living things into two kingdoms: the plant kingdom and the animal kingdom.
Phylum (Phylum): divided into divisions of the plant kingdom and the animal kingdom. Here we only introduce the division of animals:
2. Porifera (sponge)
3. Coelenterata
4. Platyhelminthes
5. Nemathelminthes
6. Annelida
7. Mollusca
8. Arthropoda
9. Echinodermata
10. Chordata
Class: Only chordates are introduced here Classification of phylum:
1. Fish class
2. Amphibian class
3. Creeping Order
4. Birds
5. Mammalia
Order: Here we only introduce the suborders of Crestozoa: there are about 5,700 species of creepers in existence, belonging to four orders , there are about 310 species in our country.
1. The order of this order - Beak leader
2. The order of turtles and turtles
3. Squamata - Lumbria
4. Squamates - Lizards
5. Squamata - Snakes
6. Crocodiles
Family: Here we only introduce the technical subfamily of turtles
Testudinata: ancient and specialized The relationship between creepers and other creepers is not yet clear, but two suborders have continued from the Mesozoic to modern times, with little change from their ancestral types.
Pleurodira: The neck is folded laterally into the shell. It is now mainly a freshwater turtle in the southern hemisphere. It was widely distributed in prehistoric times and has fossils in common.
Pelomedusidae: side-necked turtles now distributed in Africa and South America, one of which is distributed to the Arabian Peninsula.
Chelidae: side-necked turtles now scattered in Oceania and South America. Some species have very long necks, and there are fossils in Ergong.
Cryptodira suborder: includes most of the existing turtles and turtles, is widely distributed and can be seen on land, fresh water and oceans.
Chelydridae: two species of huge freshwater turtles scattered in North America. They have large heads and hook-shaped mouths, and are violent in nature.
Platysternidae: only one species, scattered in Asia. Some resemble gnat turtles but are small in size. Their classification position is approximate. Some people also include them in the gnat turtle family, Platysternidae. Chelonidae, Turtleidae, or Tortoiseidae.
Emydidae: Mainly freshwater turtles from new lands.
Bataguridae: Mainly freshwater turtles from the Old World, including some of the rarest turtles in China, and are often merged into the family Bataguridae.
Testudinidae: terrestrial turtles, distributed throughout the world except Australia, including some islands.
Dermatemydidae: There is only one species in existence, scattered in ChinaIn America, there are many fossils of Ergong.
Kinosternidae: freshwater turtles scattered in new lands.
Trionychidae: The surface is skin rather than horny scutes. It is mainly distributed in freshwater in Asia, and is also found in Africa and North America, but only fossils are found in Australia.
Carettochelyidae: freshwater turtles with skin instead of horny scutes. There is only one species in existence. They are scattered in New Guinea and northern Australia. The fossil species Softshell Turtle probably belongs to this category.
Cheloniidae: Huge turtles with horny scutes that live in the ocean.
Leatherback turtle family Dermochelyidae: a huge turtle that lives in the ocean and does not have horny scutes but is covered with skin. There is only one species in existence and it is the largest turtle in existence. Turtles.
3. Classification of turtles
The classification ranking of turtles is as follows ：
Animal (Animal) - Chordata (Chordata) - Vertebrata (Vertebrata) - Crestozoa - Turtles and Turtles, with The Burmese tortoise is an example: the Burmese tortoise belongs to: Animal, Chordata, Vertebrata, Reptilia, Testudinata, Testudinidae
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