Crocodiles are oviparous reptiles that belong to the Crocodylia family, they are semi-aquatic animals. Refering to crocodile taxonomy, there are few changes that have been presented in its morphology.
Crocodiles appeared on earth more than 200 million years ago and their morphological changes have been few. The external morphology has been preserved over time as far as evolution is concerned. They are reptiles that are currently made up of families, they are great as predators and integrate the food chain within a marine-coastal ecosystem.
This species is threatened by man, contributing to the contamination of the habitat, the sale of its skins, hunting for its scales. Research on crocodile taxonomy can have a positive impact on conservation programs. preservation of the threatened species in risk de disappearance, such as the reproduction en captivity and discovery of hybrids; so show the taxonomy of crocodiles and their needs.
Crocodile taxonomy today
It is a context that causes discrepancies in the methodical investigations of the species. According to the current revisions of the crocodile taxonomy, a recent taxonomic revision of the crocodiles of today proposed a stable systematization regarding the Taxonomic classification of animals.
There are several genera of Crocodiles, which were divided into four genera, Nile Crocodile - C. Niloticus, Alligator or alligators is a genus of sauropsids, this genus includes the four species of New World crocodiles, the genus Oopholis for the Asian, Australian and African crocodile species O.Suchus the genus Oxycrocodylus.
The four genera mentioned are gathered in the tribe Crocodylini. To the Mecistopsini tribe belong the genera Osteolaemus, Mecistops. In the tribe Gavialini, the genera Gavialis and Tomistoma.
El gender oopholis in the present is subdivided into subgenera, with the subgenus Philas for the freshwater crocodiles of appearance less in of Oopholis. Today, new species of freshwater or freshwater crocodiles have been described, including the crocodile O. Adelynhoserae got for the on de New Guinea, there is background where was qualified like a variant of the species O. Novaeguineae.
Another nueva kind of freshwater crocodile is the species O. Jackyhoserae, located to the north of the territorio of Australia and considered Firstly like a variant by O. Johnstoni.
Classification of its Taxonomy
At present, the taxonomy of crocodilians is based on a Systematization of listings stable, with their respective superior divisions. The twenty-seven (27) species evidenced nowadays of crocodiles, they are grouped in the families Crocodrylidae and Alligatoridae in of the order Crocodylia.
El group Crocodrylidae is divided into three Crocodylini, Mecistopsini and Gavialini families, and in their total they contain the eight genera mentioned in the previous paragraphs. The family alligator for his part, is divided into of subfamilies, Alligatoridae with the gender Alligator and Caimaninae with the genera Paleosuchus, Caiman and Melanosuchus.
The taxonomy of crocodile Nile Crocodylus Niloticus is one of the traditional controversial in this genre. The history taxonomy of C. niloticus comprises Eleven 11) minimized species, referred to historically and seven (7) proposed subspecies initially.
En the present day the species is recorded as only C. niloticus, but nevertheless Some molecular studies show contradictory proposing C. niloticus as a community that integrates its ancestor mixed for ambiguous species. Additionally, it has been revealed that African populations are geographically differentiated.
General characteristics of the crocodile
Crocodiles mainly distinguish the following traits:
- His body is elongated.
- The coloration varies according to the species. It varies from green to black or both are combined with each other.
- Its ferocious jaws, which have a fourth lower tooth which protrudes with its mouth closed. They are bigger and longer than the others.
- Crocodiles do not move their tongue because it is stuck to the palate.
- His entire body is covered in scales.
- They swallow stones to aid in digestion. It also serves as ballast to sink more easily.
- On the trunk of the tail it has an ice of bony plates.
- Crocodiles' legs are short and webbed, which helps them to be good swimmers.
- In the water, crocodiles can reach speeds of between 10 and 15 km per hour.
- On land they painstakingly crawl on their bellies to forage for food or mingle with other crocodiles. Although they are not very agile on the ground, they have a range of specialized movements for running away, attacking and jumping small obstacles.
Tools used in your taxonomy
The taxonomy of crocodilians has traditionally been argued in the use specific morphological as some osteological characters, which may be the belt and extremities. The methodical investigation of the skeletons cranial and appendicular, have been studied as the origin of taxonomic characters that can to improve those traditionally used in the taxonomy of the crocodile family.
El study specific to be done in tell apart the vertebrae presacral, made up of the vertebrae cervical, thoracic and lumbar muscles of crocodiles, demonstrated the high variation taxonomic, valid in these characters and their use in crocodilian taxonomy.
El crocodile from India Gavialus gangeticus presents vertebrae conspicuous presacrals that can favor at their identification. The vertebrae presacral cells that are described by region, the intervertebral interaction in this animal allows own a top mobility of the neck, optimizing also their foraging strategies when submerged in water.
Molecular tools like bar code of hereditary has become a tool for the study and management of biology data, implemented in studies of the taxonomy of crocodiles. Additionally, other molecular markers, such as the DNA sequence in a fragment, have been used in the classification of species that are the same in their morphological structure and have as a consequence the discovery of hybrids.
These molecular tools are of benefit in the taxonomy of the family, which can boost strategies of supervivencia for crocodiles today. The mitochondrial genes Cytochrome Oxidase I and Cytochrome B are potential molecular markers used in taxonomic studies to identify crocodiles.
Taxonomic needs in the group
La necesidad in crocodilian taxonomy is based on the research projects. of additional aspects, which can integrate taxonomic studies in this ancient family of reptiles.
Structural aspects, such as scale morphology using discarded electron microscope equipment, consist of potential morphological characters, which can perfect la identity of the current species. To its time, anatomy internal is an invaluable source of morphological characters of imported which however was not explored.
Evidently molecular biology studies, consist of necessary to be able to expand the molecular markers carrying them out in the crocodilian taxonomy, in this way way to have a good result in The programs of reproduction en captivity of species in peligro de extinction. The wrong taxonomic identity of the crocodile can harm conservation programs. preservation especially in morphologically identical individuals.
extinct crocodiles
Regarding the taxonomy of extinct crocodiles, it is fair to emphasize than crocodiles, is the current symbol of a varied group of reptiles, adversaries of the dinosaurs of the Triassic period (Pseudosuchia). An extinct subfamily of crocodiles from the lineage Crocodylidae was the Tomistominae. In mid-2008, fossils of the species Gavialosuchus americanus were recorded at on de Costa Rica (Miocene and Pliocene early). this kind of crocodile solo had been registered with precedence in South America Public chat and Africa, thus extending its distribution ancient.
Human-Crocodile Conflict
Crocodile attacks on humans are infrequent, but loss of life is recorded every year, especially when they get too close and especially in remote areas where this reptile lives. The marine crocodile (Crocodylus porosus) is considered the most dangerous, followed by the Nile crocodile (Crocodylus niloticus), the latter eats all kinds of fish and even hippopotamuses, this species can also survive in the sea.
In Mexico in the 80s, illegal hunting resulted in the extinction of large families in some regions; but thanks to the work of organized groups of conservationists, environmentalists, communities and wildlife protectors they managed to restore the species throughout the country, currently the number of species that existed has been exceeded and it is natural to see crocodiles move around in rainy seasons. flooded urban areas.
Crocodile hunting is widespread due to the value of its skin, which is used to make belts, wallets and travel bags, and its meat, which is considered a delicacy in many places.
An effective measure is to protect the habitat where they lay their eggs in order to preserve the species. If, for example, the Nile crocodiles disappeared, there would be such an imbalance in the ecosystem that the rivers would dry up.
Like any wild animal, when threatened, its instinct is to defend itself, so it is best not to provoke it, flee in a straight line and never zigzag, because that is how it is a very skilled hunter. Signs that warn of the presence of crocodiles, especially in the water, regardless of the size of the animal, should never be overlooked.
In U.S. Florida, is the habitat of the Alligator toAmerican (Theremississippiensis gator) is numerous and inhabits areas where humans reside; Five cases of crocodile bite accidents are recorded each year.
It must be borne in mind that the conflict between human and crocodile will exist due to its nature, since humanity is the one that occupied its habitat, it only remains to take Environmental awareness and the pertinent precautions to avoid accidents.