Birds are vertebrate animals with the body covered with feathers and with the forelimbs transformed into wings, and reproduce by eggs. Its complexity is almost at the top of the Animal Kingdom.
They have great independence from the environment, which allows them to colonize all types of environments.
They have a skin with a thin but impermeable epidermis aided by the lining of feathers, this prevents the evaporation of water from the internal environment is important. In addition, the excretory system, consisting of a pair of kidneys located in the pelvic region, with two short ureters that flow directly into the sewer, eliminates uric acid in the form of a white paste that is expelled along with feces. Water loss is minimal and allows birds to colonize extremely arid environments.
Another factor that limits life in terrestrial environments is temperature. The birds control it by keeping their body at a high and constant temperature, obtained from internal metabolism. The internal temperature is close to 40 º C. The outer covering of feathers, and breathing are the means that are worth to regulate that temperature since the birds lack sweat glands. The feathers appear in birds primarily to prevent excessive heat leakage and secondarily as parts for the flight. They are scales, modified dermal that come from those that the reptiles had.
La mayoría de ellas están adaptadas para volar.
Existen actualmente unas 6.500 especies.
There are bird species that migrate, coinciding with the changing seasons.
The common characters are:
- They are animals of constant temperature and with pulmonary respiratory system very modified by their adaptation to flight, which requires great ventilation.
- Five air sacs depend on each lung that extend between the different organs and penetrate even inside some bones, allowing them to reduce the weight of
your body, which extend in some cases to the inside of the bones.
They also act as refrigerants during the flight.
- The mouth is beak-shaped, without teeth.
Some have siringe, an organ they use to emit trills.
- The bird's eye is usually very developed, calculating that it is 100 times higher than that of man.
- Birds have a crop where they store food, stomach and gizzard with muscles that crush the food.
- Their fertilization is internal and they reproduce by eggs that hatch.
- Some birds the nests, build nests for their young.
Others, the nests, do not need them.
- All birds have wings.
The flight of birds depends on their wings.
The wings of the birds are sustaining and propelling.
Glider birds take advantage of updrafts.
Long, pointed wings allow great speed and autonomy.
Short wings are suitable for short flights.
For example, its short wings allow a very rapid movement to the hummingbird.
The wings and skin of a bird are covered with feathers.
To move the wings, the birds have large pectoral muscles that, when contracted, produce the descending beat of the wings.
Then the traction of these muscles is reduced and the supracoracoid acts, pulling the pulley-shaped tendon and raising the wings.
The structure of the feathers is complex. They consist of a central axis, the calamus or rachis, and a wide and flattened portion of the banner, which is made up of numerous beards, which in turn divide many small chins. The chins on one side of the beard carry numerous small hooks or crochet hooks, which are attached to the nearby chins giving the normal texture of the feathers, continuous and elastic.
A structure as complex and delicate as a feather is, it requires care by the bird and in general they all spend a good part of the day keeping their plumage in good condition.
Basically, plumage care consists in carefully distributing the fat secretion of the uropigial gland, which is located above the tailbone.
With a slight pressure of the beak, the gland secretes a certain amount of fat that is then distributed by plumage.
The type of feathers described corresponds to the typical feathers, of contour or profile, since they are the ones that give their external shape to the bird. There are other simpler types of pens.
The filoplumas, have the appearance of hairs, due to the atrophy of the beards; they can have tactile function or located around the peak act as collector of insects in some species.
The down (nibs), formed by atrophy of the part of the calamus that supports the beards, whose function is as thermal insulators, the elaboration of nests, etc.
The feathers shirts are part of the wings as they have a structure that gives them lightness and solidity. They are the ones that hold the birds in the air.
The rudders or tail rectrices work as a rudder, brake and counterweight.
The beak has numerous forms, it is the part that presents the greatest variability in birds, changing its shape according to the biotope and ecological niche used by each species. This formed by the extension of the jaws and covered by two modified scales.
Said corneal lining has a continuous growth, to compensate for the wear suffered, which in certain groups, such as woodpeckers (spicy), is very high (up to 0.22 mm. per day).
In relation to the length of the head, the beak is considered long, when it is longer than the rest of the head, and short when it is shorter.
Regarding the form it can be:
- hooked, when it is curved and sharp (carnivores)
- crossed, when both mandibular teakes intersect each other (piquituertos);
- compressed, when it is narrower than tall (gulls)
- depressed, if it is wider than tall (ducks)
- in chisel when it is long and pointed (woodpeckers)
- conirrostro, if it is conical and strong (granivorous)
- acute or acutirrostro, if pointed with slow decrease in thickness (insectivorous)
- lamelado, if it has filtering sheets on its edges (ducks)
- spatulated, when it is wider at its distal end than at the base (spoon duck)
The great variety of birds makes their classification very difficult, since to the diversity of the environments they inhabit, we must add the variety of shapes and colors that can vary greatly within the same species according to sex or time.
The Bird Class is classified into Orders and Families, in this table a quick approximation has been made by bringing them together in groups that have some common characteristic.
They can also be classified in other ways such as mountain, forest, marine, riverbank, marsh, poultry, canoe, etc.
- NO FLYERS (Ratites)
- The ratite or non-flying birds have very small upper limbs and unable to fly and also lack a keel-shaped sternum, which is where the large pectoral muscles of the flight are inserted.
They are very primitive birds about 80 cm long, including the long beak.
Its wings are almost non-existent.
They have short, sturdy legs, adapted for the race.
In this order several species of kiwis are included, very gentle birds that look for the food at night.
They have the nostrils at the tip of the beak.
Kiwi lives in New Zealand. They lay an egg of disproportionate size, almost a third the size of the animal.
The runners, also called struciforms are non-flying birds whose small wings are not functional.
They are adapted for the race, with long and sturdy legs with two or three vigorous fingers.
To this order of birds belong the ostrich, the ñandú, the emu of Australia and the cassowary of New Guinea.
The ostrich is the biggest bird of the runners, with 2 meters high and 150 kg in weight, and reaches 60 km per hour in its career.
The ostrich's foot has two fingers.
The ñandú lives in South America, extending into the Pampas, Patagonia and the Andes.
The foot of the cassowary has three fingers, one of them with a very long nail that can be used as a defense.
- FLYERS (Fairing)
They are gaviformes the colimbos, diving birds excellently adapted for the aquatic life.
The somormujos and the zampullines are swimming and diving birds that live in small groups around the world.
The somberujo lavaco performs complicated dances in the mating season.
They are seabirds with webbed feet, compressed beak formed by several pieces, corvado, long and narrow wings, excellent flying, extended by all the seas of the world.
The albatross, the shearwater, the petrel, the cloth, the fulmar, etc. are of this order.
Swimmers with webbed feet with the four fingers, all united with a membrane. Many dive from the air to fish under water.
This bird order groups several families: the pelicans, frigates, gannets, phaetons, cormorants, aningas, etc.
The sphenyciform birds group the silly birds, also called penguins.
They are seabirds, divers, with long beaks, short legs and wings adapted to swimming, which dominate perfectly.
- Pay them
Seagull-like seabirds, characterized by white flashes from the center of the wings, noticeable in flight. Their flight is faster than that of seagulls.
They are diving seabirds with webbed feet and short wings.
Among them the alca, arao and common puffin, beak with bright color that loses in the winter season.
Striking, with a strong beak, with very delayed palmípedo feet and small buzzing wings when flying over the sea.
Erect, they superficially remember the penguins.
They are water birds with a wide beak that has corneal blades on the edges.
They have webbed feet and varied and rich plumage.
To the anseriformes belong ducks, ants, swans, geese, geese and ducks.
Grouped under the generic designation of mosquitoes, there are usually riverside birds, with long neck, legs and beak, adapted to look for food in
Shallow water without getting your body wet. The following orders can be counted among the mosquitoes: ciconiformes, gruiformes and caradriformes.
The ciconiformes are birds adapted to shallow waters with a neck, beak and very long legs.
Among the best known are the ibis stork, spatula, marabou, jabirú, shoe spike, hammer bird, heron, egret, avetoro, cattle egret, etc.
The gruiformes groups preferably land birds, of varied appearance, some very beautiful. Many live in riverbanks or swampy areas, and others rarely fly. These include cranes, bustards, scratches, water cock, shrimp, etc.
The caradriformes include birds of varied forms and customs. They generally have aquatic habits. Among its species are the plover, chorlitejo, lapwing, scholarship, turf stones, jacanas, oystercatcher, walkways, etc.
They are birds distributed all over the world with about 250 species.
Medium or large in size, solid appearance, sturdy legs suitable for walking and running and strong fingernails for digging.
The wings are short and wide, the beak strong and slightly curved, with an operculum that partially covers the nostrils while digging.
They often have ridges and chins, and their plumage is vividly colored, especially in males.
They feed preferably on grain.
They are medium sized birds that are distinguished by having a fleshy membrane or "wax" in their beaks. They are excellent flying and feed on grain.
They have a dilated crop that, at the time of reproduction, secretes a milky liquid, with which they feed their young.
To this order belong the pigeon doves, domestic pigeons, guras, turtledoves, bargains, etc.
The pigeons have a fleshy mass or "wax" at the base of the beak where the nostrils open.
They are of varied dimensions and look very different. They have two fingers directed forward and two backwards, adapted to climb trunks
and move between the branches. The spicy or peaks comprise all picapinos, and are distributed all over the world.
Other families include jacamar, indicator, and toucan, with their different species.
Carpenter's peaks have a long, narrow tongue with a serrated tip, which can be thrown and introduced into tree holes to capture larvae.
Cuckoo or cuckoo are the most typical representatives of this order. They almost always feed on insects and caterpillars. Numerous species practice
a nest-parasitism that consists of depositing eggs in the nests of other species so that chickens are incubated, which develop rapidly and
they expel the original eggs from the nest.
They are birds birds, among which are parrots, macaws, parrots, cockatoos. parakeets, etc.
All have a strong and curved beak, ending in a very sharp tip, with the articulated and movable upper jaw.
Each foot has two fingers forward and two back, with those who can grab the branches and climb through them also helping with the beak.
They feed on fruits, seeds, roots and small animals. Some species can learn to articulate words with remarkable clarity.
It is a very diverse group of birds of prey or raptors that feed on meat.
They have strong claws and hooked and robust beak, with sharp edges, suitable for tearing their prey. The flight is powerful, broad and sustained. Some
They usually rise with their prey in the claws; others attack their victims at speeds exceeding 100 km per hour.
Some feed on live prey and others are of the scavenger regime. His sense of sight is amazingly developed.
Among them are the condor, the vultures and bearded vultures, the eagles, eaglets, alcotanes, azor, falcon, etc.
They are birds of nocturnal customs, although some also fly and hunt during the day.
Its wings are long and rounded, fast and quiet, very suitable for night hunting.
They have a large head, which can rotate 180 degrees, with large eyes in the frontal position and have an extraordinary vision in the dark.
The beak is hooked and the claws are typical of predatory birds.
They feed on small mammals and reptiles.
To this Order belong owls, owls, carabs, autillos, owls, etc.
It is a group of nocturnal birds with large jaws surrounded by long sensitive bristles.
Most species are tropical and almost always feed on insects that hunt on the fly.
To this Order belong the chotacabras, which inhabit the temperate forests of Eurasia, and the podargos, the urutau and the guácharo, from tropical areas.
The guácharo lives in caves in the South American jungle and uses, both to guide himself in the dark and to locate his prey, the same echolocation system as bats.
This order includes two groups of very different aspect the swifts and hummingbirds.
Both groups have in common their thin and narrow wings, adapted for a quick flight.
Swifts usually fly at about 90 km / h. but they can sometimes exceed 200 km / h. Hummingbirds live in tropical forests, are small and feed
of the nectar of flowers. Their flight is exceptional as they can move in any direction and even stand in the air.
Swifts are skilled hunters on the fly. Their claws allow them to cling to the walls.
The most representative is the Central American Quetzal of beautiful plumage.
Figure on the flag of Guatemala.
All have legs adapted for arboreal life, but useless for walking on the ground.
Its species are very varied and live in tropical and subtropical regions. Among them known the bee-eater, the kingfisher, the kalao, the hoopoe, the ratchet, the niomoto, etc.
- Birds or passerines
This order is the most numerous, with about 5,000 species with many different characters.
They are generally small in size, with a slender body, small head and beak of varied shapes, adapted to the type of feeding.
Legs adapted for grip and permanence in the branches by a tendon mechanism.
The mechanism of the legs of the birds is that when perching on the branches, a tendon closes the leg preventing the bird from falling.
To open it you have to rise slightly.
Soft plumage, abundant and of different colors.
They are agile, vivacious and resistant.
They have syringes that allow them to modulate songs and trills, some very harmonious.
They feed on seeds, grains, fruits and insects.
They lay eggs in nests built in trees or on the ground.
The evolution of the Birds
The most primitive birds develop from certain reptiles.
The oldest reptile fossil but with bird characteristics is the archaeoptera.
It appeared on Earth approximately 100 million years ago. Like other contemporary reptiles, archaepterix still had teeth, three fingers with claws on the elbow of the wing and a vertebrate tail. The archaepterix was the size of a crow, it was covered with feathers: a precursor capable of planning from one tree to another rather than actually flying.
Other later fossil birds such as ichiornis and hesperornis, who lived on the edge of the water and fly badly, mark the path that the evolution of the birds followed, which is not they developed as a class until the disappearance of dinosaurs 65 million years ago.
Other information about fauna in Aragón:
A small list of species in Aragon would be the following:
Also Aragon enjoys a diverse and varied Nature where passing by plants,
animals, Geology, or landscapes we can arrive at a fantastic bestiario that lives in its monuments.
The information will not be complete without a stroll by its three provinces, with shutdown in some of its spectacular landscapes like
Ordesa, the Moncayo, Monegros
or by opposition the Ebro.
Also you can dedicarte to the intangible ones: from the legend compilation
that also does to universal 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.
zoology, reproduction, physiology, metazoans, celomados, chordates, vertebrates, birds, mammals, ecology, zoogeography,
Water, humidity, wetlands, sea, river, mountain, air, food