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Albatrosses, of the biological family Diomedeidae, are large seabirds allied to the procellariids, storm-petrels and diving-petrels in the order Procellariiformes (the tubenoses). They range widely in the Southern Ocean and the North Pacific. They are absent from the North Atlantic, although fossil remains show they once occurred there too and occasional vagrants are found. Albatrosses are among the largest of flying birds, and the great albatrosses (genus Diomedea) have the largest wingspans of any extant birds, reaching up to 12 feet (3.7 m). The albatrosses are usually regarded as falling into four genera, but there is disagreement over the number of species.
Albatrosses are highly efficient in the air, using dynamic soaring and slope soaring to cover great distances with little exertion. They feed on squid, fish and krill by either scavenging, surface seizing or diving. Albatrosses are colonial, nesting for the most part on remote oceanic islands, often with several species nesting together. Pair bonds between males and females form over several years, with the use of 'ritualised dances', and will last for the life of the pair. A breeding season can take over a year from laying to fledging, with a single egg laid in each breeding attempt. A Laysan albatross, named "Wisdom" on Midway Island is recognized as the oldest wild bird in the world; she was first banded in 1956 by Chandler Robbins.
Of the 21 species of albatrosses recognised by the IUCN, 19 have been threatened with extinction. Numbers of albatrosses have declined in the past due to harvesting for feathers, but today the albatrosses are threatened by introduced species, such as rats and feral cats that attack eggs, chicks and nesting adults; by pollution; by a serious decline in fish stocks in many regions largely due to overfishing; and by long-line fishing. Long-line fisheries pose the greatest threat, as feeding birds are attracted to the bait, become hooked on the lines, and drown. Identified stakeholders such as governments, conservation organisations and people in the fishing industry are all working toward reducing this bycatch.
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Although the word jackal has often been used historically to refer to many small- to medium-sized species of the wolf genus of mammals, Canis, today it most properly and commonly refers to three species: the black-backed jackal, the side-striped jackal of sub-Saharan Africa, and the golden jackal of northern Africa and south-central Eurasia. The black-backed and side-striped jackals are more closely related to each other than they are to the golden jackal, which is closer to wolves, dogs, and coyotes.
Jackals and coyotes (sometimes called the "American jackal") are opportunistic omnivores, predators of small- to medium-sized animals and proficient scavengers. Their long legs and curved canine teeth are adapted for hunting small mammals, birds, and reptiles, and their large feet and fused leg bones give them a physique well-suited for long-distance running, capable of maintaining speeds of 16 km/h (9.9 mph) for extended periods of time. Jackals are crepuscular, most active at dawn and dusk.
Their most common social unit is that of a monogamous pair which defends its territory from other pairs by vigorously chasing intruding rivals and marking landmarks around the territory with their urine and feces. The territory may be large enough to hold some young adults which stay with their parents until they establish their own territories. Jackals may occasionally assemble in small packs, for example, to scavenge a carcass, but they normally hunt either alone or in pairs.
Industry:Animals
An alligator is a crocodilian in the genus alligator of the family Alligatoridae. There are two living alligator species: the American alligator (Alligator mississippiensis) and the Chinese alligator (Alligator sinensis). In addition, several extinct species of alligator are known from fossil remains. Alligators first appeared during the Oligocene epoch about 37 million years ago.
The name alligator is an anglicized form of el lagarto, the Spanish term for "the lizard", which early Spanish explorers and settlers in Florida called the alligator.
Industry:Animals
An alpaca (Vicugna pacos) is a domesticated species of South American camelid. It resembles a small llama in appearance.
There are two breeds of alpaca; the suri alpaca and the huacaya alpaca.
Alpacas are kept in herds that graze on the level heights of the Andes of southern Peru, northern Bolivia, Ecuador, and northern Chile at an altitude of 3,500 m (11,500 ft) to 5,000 m (16,000 ft) above sea level, throughout the year. Alpacas are considerably smaller than llamas, and unlike llamas, they were not bred to be beasts of burden, but were bred specifically for their fiber. Alpaca fiber is used for making knitted and woven items, similar to wool. These items include blankets, sweaters, hats, gloves, scarves, a wide variety of textiles and ponchos in South America, and sweaters, socks, coats and bedding in other parts of the world. The fiber comes in more than 52 natural colors as classified in Peru, 12 as classified in Australia and 16 as classified in the United States.
In the textile industry, "alpaca" primarily refers to the hair of Peruvian alpacas, but more broadly it refers to a style of fabric originally made from alpaca hair, but now often made from similar fibers, such as mohair, Icelandic sheep wool, or even high-quality English wool. In trade, distinctions are made between alpacas and the several styles of mohair and luster.
An adult alpaca generally is between 81 and 99 cm in height at the withers. They usually weigh between 48 and 84 kg (106 and 185 lbs).
Industry:Animals
An anaconda is a large, non-venomous snake found in tropical South America. Although the name actually applies to a group of snakes, it is often used to refer only to one species in particular, the common or green anaconda, Eunectes murinus, which is one of the largest snakes in the world.
Anaconda may refer to:Although the name refers to a snake found only in South America, the name commonly used in Brazil is sucuriyu or sucuriuba. The South American names anacauchoa and anacaona were suggested in an account by Peter Martyr d'Anghiera but the idea of a South American origin was questioned by Henry Walter Bates who, in his travels in South America, failed to find any similar name in use. The word anaconda is derived from the name of a snake from Ceylon that John Ray described in Latin in his Synopsis Methodica Animalium (1693) as serpens indicus bubalinus anacandaia zeylonibus, ides bubalorum aliorumque jumentorum membra conterens. Ray used a catalogue of snakes from the Leyden museum supplied by Dr. Tancred Robinson but the description of its habit was based on Andreas Cleyer who in 1684 described a gigantic snake that crushed large animals by coiling and crushing their bones. Henry Yule in his Hobson-Jobson notes that the word became more popular due to a piece of fiction published in 1768 in the Scots Magazine by a certain R. Edwin. Edwin described a tyger being crushed and killed by an anaconda when in fact tigers never occurred in Sri Lanka. Yule and Frank Wall noted that the snake was in fact a python and suggested a Tamil origin anai-kondra meaning elephant killer. A Sinhalese origin was suggested by Donald Ferguson who pointed out that the word Henakandaya (hena lightning and kanda stem/trunk) was used for the small whip snake (Ahaetulla pulverulenta) and somehow got misapplied to the python before myths were created.
Industry:Animals
An arthropod is an invertebrate animal having an exoskeleton (external skeleton), a segmented body, and jointed appendages. Arthropods are members of the phylum Arthropoda (from Greek ἄρθρον árthron, "joint", and πούς pous (gen. podos), i.e. "foot" or "leg", which together mean "jointed leg"), and include the insects, arachnids, and crustaceans. Arthropods are characterized by their jointed limbs and cuticles, which are mainly made of α-chitin; the cuticles of crustaceans are also biomineralized with calcium carbonate. The rigid cuticle inhibits growth, so arthropods replace it periodically by moulting. The arthropod body plan consists of repeated segments, each with a pair of appendages. Their versatility has enabled them to become the most species-rich members of all ecological guilds in most environments. They have over a million described species, making up more than 80% of all described living animal species, some of which, unlike most animals, are very successful in dry environments. They range in size from microscopic plankton up to forms a few meters long.
Arthropods' primary internal cavity is a hemocoel, which accommodates their internal organs, and through which their blood circulates; they have open circulatory systems. Like their exteriors, the internal organs of arthropods are generally built of repeated segments. Their nervous system is "ladder-like", with paired ventral nerve cords running through all segments and forming paired ganglia in each segment. Their heads are formed by fusion of varying numbers of segments, and their brains are formed by fusion of the ganglia of these segments and encircle the esophagus. The respiratory and excretory systems of arthropods vary, depending as much on their environment as on the subphylum to which they belong.
Their vision relies on various combinations of compound eyes and pigment-pit ocelli: in most species the ocelli can only detect the direction from which light is coming, and the compound eyes are the main source of information, but the main eyes of spiders are ocelli that can form images and, in a few cases, can swivel to track prey. Arthropods also have a wide range of chemical and mechanical sensors, mostly based on modifications of the many setae (bristles) that project through their cuticles.
Arthropods' methods of reproduction and development are diverse; all terrestrial species use internal fertilization, but this is often by indirect transfer of the sperm via an appendage or the ground, rather than by direct injection. Aquatic species use either internal or external fertilization. Almost all arthropods lay eggs, but scorpions give birth to live young after the eggs have hatched inside the mother. Arthropod hatchlings vary from miniature adults to grubs and caterpillars that lack jointed limbs and eventually undergo a total metamorphosis to produce the adult form. The level of maternal care for hatchlings varies from nonexistent to the prolonged care provided by scorpions.
The versatility of the arthropod modular body plan has made it difficult for zoologists and paleontologists to classify them and work out their evolutionary ancestry, which dates back to the Cambrian period. From the late 1950s to late 1970s, it was thought that arthropods were polyphyletic, that is, there was no single arthropod ancestor. Now they are generally regarded as monophyletic. Historically, the closest evolutionary relatives of arthropods were considered to be annelid worms, as both groups have segmented bodies. This hypothesis is now largely rejected, with annelids and molluscs forming the superphylum Lophotrochozoa. Many analyses support a placement of arthropods with cycloneuralians (or their constituent clades) in a superphylum Ecdysozoa. Overall however, the basal relationships of Metazoa are not yet well resolved. Likewise, the relationships between various arthropod groups are still actively debated.
Arthropods contribute to the human food supply both directly as food, and more importantly as pollinators of crops. Some specific species are known to spread severe disease to humans, livestock, and crops.
Industry:Animals
An earthworm is a tube-shaped, segmented animal commonly found living in soil, that feeds on live and dead organic matter. Its digestive system runs through the length of its body. It conducts respiration through its skin. An earthworm has a double transport system composed of coelomic fluid that moves within the fluid-filled coelom and a simple, closed blood circulatory system. It has a central and a peripheral nervous system. The central nervous system consists of two ganglia above the mouth, one on either side, connected to a nerve cord running back along its length to motor neurons and sensory cells in each segment. Large numbers of chemoreceptors are concentrated near its mouth. Circumferential and longitudinal muscles on the periphery of each segment enable the worm to move. Similar sets of muscles line the gut, and their actions move the digesting food toward the worm's anus.
Earthworms are hermaphrodites—each individual carries both male and female sex organs. As an invertebrate, it lacks a skeleton, but it maintains its structure with fluid-filled coelom chambers that function as a hydrostatic skeleton."Earthworm" is the common name for the largest members of Oligochaeta (which is either a class or a subclass depending on the author) in the phylum Annelida. In classical systems, they were placed in the order Opisthopora, on the basis of the male pores opening posterior to the female pores, though the internal male segments are anterior to the female. Theoretical cladistic studies have placed them, instead, in the suborder Lumbricina of the order Haplotaxida, but this may again soon change. Folk names for the earthworm include "dew-worm", "rainworm", "night crawler", and "angleworm" (due to its use as fishing bait).
Larger terrestrial earthworms are also called megadriles (or big worms), as opposed to the microdriles (or small worms) in the semiaquatic families Tubificidae, Lumbriculidae, and Enchytraeidae, among others. The megadriles are characterized by having a distinct clitellum (which is more extensive than that of microdriles) and a vascular system with true capillaries.
Industry:Animals
An egret is any of several herons, most of which are white or buff, and several of which develop fine plumes (usually milky white) during the breeding season. Many egrets are members of the genera Egretta or Ardea which also contain other species named as herons rather than egrets. The distinction between a heron and an egret is rather vague, and depends more on appearance than biology. The word "egret" comes from the French word "aigrette" that means both "silver heron" and "brush," referring to the long filamentous feathers that seem to cascade down an egret's back during the breeding season.
Several of the egrets have been reclassified from one genus to another in recent years: the Great Egret, for example, has been classified as a member of either Casmerodius, Egretta or Ardea.
In the 19th and early part of the 20th century, some of the world's egret species were endangered by relentless plume hunting, since hat makers in Europe and the United States demanded large numbers of egret plumes, leading to breeding birds being killed in many places around the world.
Several Egretta species, including the Eastern Reef Egret, the Reddish Egret and the Western Reef Egret have two distinct colours, one of which is entirely white. Little Blue Heron has all-white juvenile plumage.
Industry:Animals
An otter is any of 13 living species of semiaquatic (or in the case of the sea otter, aquatic) mammals that feed on fish and shellfish, and also other invertebrates, amphibians, birds and small mammals.
The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, badgers, wolverines, and polecats.
Industry:Animals
An ox (plural oxen), also known as a bullock in Australia, New Zealand and India, is a bovine trained as a draft animal. Oxen are commonly castrated adult male cattle; castration makes the animals easier to control. Cows (adult females) or bulls (intact males) may also be used in some areas.
Oxen are used for plowing, for transport (pulling carts, hauling wagons and even riding), for threshing grain by trampling, and for powering machines that grind grain or supply irrigation among other purposes. Oxen may be also used to skid logs in forests, particularly in low-impact, select-cut logging.
Oxen are usually yoked in pairs. Light work such as carting household items on good roads might require just one pair, while for heavier work, further pairs would be added as necessary. A team used for a heavy load over difficult ground might exceed nine or ten pairs.
Industry:Animals
