Mammals are the most evolved animals of all that exist, with some 5,000 different species worldwide.
Its size ranges from 4 centimeters for the dwarf shrew to 30 meters for the blue whale.
This evolution and variety have allowed them to conquer all environments on earth, both the continents and the seas and air.
The common characters are:
The lower jaw is made up of a single dental bone.
The epiglottis is a valve that closes the entrance to the trachea.
A muscular septum, the diaphragm, separates the abdominal cavity from the thorax.
Almost all mammals have seven cervical vertebrae, regardless of the length of the neck.
The ear of mammals has three ossicles:
Some mammals have hair changes, depending on the seasons of the year.
The horns are hollow, bony protrusions that emerge from the skull and never fall off.
Some horns are made up of modified and fused hairs.
> Antlers appear as buds on the skull and grow as spongy tissue that calcifies or hardens into bone.
The antlers are shed annually and new ones come out.
Mammals have viviparous reproduction (except monotremes).
Its fertilization is internal through the copulatory organ of the male.
The baby before being born develops gradually in the mother's body, within several envelopes, and receives food from her through the placenta, and is protected by a bag full of water: the amnion.
After being born the young are suckled, taking milk from the mother's mammary glands.
In this table you can see the differences between the gestation periods and the number of offspring of a series of mammalian species:
|Gestation periods and offspring of some mammals|
|House mouse||9 days||5-7 pups|
|House cat||2 months||4-6 pups|
|Dog||2 months||2-4 pups|
|Porcupine||2 months||2-4 pups|
|Deer||2 months||1-3 calves|
|Male||9 months||1 calf|
|Whale||10-12 months||1 calf|
|Elephant||24 months||1 baby|
Due to the persecution they have been subjected to, they are elusive and difficult to observe. We could do the following small classification:
|ORDER||FAMILY||Genus and species||Common name|
|Insectivores||Erinaceids||Erinaceus europaeus||Common hedgehog|
|Tálpidos||Talpa europaea||Common mole|
|Galemys pirenaicus||Pyrenean Desman|
|Sorícidos||Crocidura russula||Common shrew|
|Sorex araneus||Forest shrew|
|Sorex alpinux||Alpine shrew|
|Neomys fodiens||Water shrew|
|Neomys anomalus||Cabrera's water shrew|
|Suncus atruscus||Dwarf mosgaño or Shrew|
|Lagomorphs||Leporidae||Oryctolagus cuniculus||Common Rabbit|
|Leptus europaeus||European Hare|
|Leptus timidus||Variable hare|
|Rodents||Sciurids||Sciurus vulgaris||Red squirrel|
|Glis glis||Gray dormouse|
|Microtids||genus Pitymys: 3 species||Voles|
|Clethrionomys glareolus||Red vole|
|Microtus nivalis||Snowy Rat|
|Microtus arvalis||Peasant mouse|
|Microtus cabrerae||Mediterranean rat|
|Microtus agrestis||Wild mouse|
|Arvicola sapidus||Water rat|
|Arvicola terrestris||Northern water rat|
|Murids||Rattus rattus||Black rat|
|Rattus norvegicus||Gray or common rat|
|Apodemus flavicolis||Fawn mouse|
|Apodemus sylvaticus||Field mouse|
|Mus musculus||House mouse|
|Mus spretus||Wild mouse|
|Ursidae||Ursus arctos||Brown bear|
|Felidae||Lynx parnina||Iberian lynx ???|
|Lynx lynx||European lynx ???|
|Artiodactyls||Suidos||Sus scrofa||Wild boar|
|Deer||Dama dama||Fallow deer|
|Capreola capreola||Roe deer|
|Bovidae||Capra pyrenaica||Mountain goat|
A small list of species in Aragon would be the following:
images about the fauna in Aragon.|
photographs on invertebrates.
beneficial animals for agriculture.
Ebro | Landscape | Monegros | Moncayo | Ordesa
Zh2o | Photografies
Document | Nature in Aragon
The pasapues project is an extension of the Aragón project is like that, and tries to collect and relate all possible types of documentary information about Aragon: texts, books, articles, maps, illustrations, photographs, narrations, etc., and proceed to its publication and diffusion.
Mammals Vertebrates Animal Kingdom. Fauna. Zoology, reproduction, physiology, metazoans, coelomates, chordates, vertebrates, ecology, zoogeography, water, river, mountain
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