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Altricial, meaning "requiring nourishment", refers to a pattern of growth and development in organisms which are incapable of moving around on their own soon after hatching or being born. The word is derived from the Latin root alere meaning "to nurse, to rear, or to nourish", and refers to the need for young to be fed and taken care of for a long duration.

In bird and mammal biology, altricial species are those whose newly-hatched or -born young are relatively immobile, lack hair or down, and must be cared for by adults; closed eyes are common, though not ubiquitous. Altricial young are born helpless and require care for a comparatively long time. Among birds, these include, for example, herons, hawks, woodpeckers, owls and most passerines. Marsupials and most rodents are altricial. Cats, dogs, and humans are some of the most well-known altricial organisms.

At the opposite end of the spectrum are precocial animals in which the young have open eyes, have hair or down, have large brains, and are immediately mobile and somewhat able to flee from, or defend themselves against, predators. For example, with ground-nesting birds such as ducks or turkeys, the young are ready to leave the nest in one or two days. Among mammals most ungulates are precocial, being able to walk almost immediately after birth.

Different animals employ different precocial and altricial strategies; there is no clear distinction between the two states, and a wide range of intermediate states. The ability of the parents to obtain nutrition and contribute to the pre-natal and post-natal development of their young appears to be associated.

Precocial birds are able to provide protein-rich eggs and thus their young hatch in the fledgling stage – able to protect themselves from predators (ducks or turkeys) and the females have less involvement post-natal. Altricial birds are less able to contribute nutrients in the pre-natal stage; their eggs are smaller and their young still in need of much attention and protection from predators. This may be related to r/K selection; however, this association fails with a number of cases.

In the case of mammals it has been suggested that large adult body sizes favor production of large, precocious young, which develop with a long gestation period. Large young may be associated with long lifespan, extended reproductive period, and reduced litter size. It has been suggested that altricial strategies in mammals may be favoured if there is a selective advantage to mothers that are capable of resorbing embryos in early stages of development.

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Animal hoarding is a mental illness recognized as a psychological condition. It is considered a variant of obsessive-compulsive disorder rather than deliberate cruelty towards animals. Animal hoarding involves keeping higher than usual numbers of animals as pets without having the ability to properly house or care for them, while at the same time denying this inability. Hoarders are deeply attached to their pets, and find it extremely difficult to let the pets go. They typically cannot comprehend that they are harming their pets by failing to provide them with proper care. Hoarders tend to believe that they provide the right amount of care for their pets. The American Society for the Prevention of Cruelty to Animals provides a "Hoarding Prevention Team", which works with hoarders to help them attain a manageable and healthy number of pets.

Animal hoarding is also a serious animal welfare issue, cats - in communities throughout the United States. Hoarders keep abnormally large numbers of animals for which they may not provide even the most basic care. The sometimes hundreds of dogs or cats kept by a single hoarder generally show signs of neglect such as severe malnutrition, untreated medical conditions including open sores, cancers, and advanced dental and eye diseases, and severe psychological distress. In 80 percent of the cases studied, authorities found either dead or severely ill animals in hoarders' homes. Animal hoarding is also a public health threat, as hoarding creates highly unsanitary conditions on the properties of hoarders.

Many states have no legal definition for animal hoarding (though localities may have a limit of the number and types of pets), and many people are unaware of the severity of neglect in typical hoarding situations. Animals rescued from hoarders must often be cared for at the rescuer's expense, and the high cost of doing this can also act as a disincentive for prosecuting hoarding cases. These factors can make it a lengthy and challenging legal process to secure a verdict against an animal hoarder charged with animal cruelty.

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Mimicry, in biology, phenomenon characterized by the superficial resemblance of two or more organisms that are not closely related taxonomically. This resemblance confers an advantage—such as protection from predation—upon one or both organisms by which the organisms deceive the animate agent of natural selection. The agent of selection (which may be, for example, a predator, a symbiont, or the host of a parasite, depending on the type of mimicry encountered) interacts directly with the similar organisms and is deceived by their similarity. This type of natural selection distinguishes mimicry from other types of convergent resemblance that result from the action of other forces of natural selection (e.g., temperature, food habits) on unrelated organisms.

In the most-studied mimetic relationships, the advantage is one-sided, one species (the mimic) gaining advantage from a resemblance to the other (the model). Since the discovery of mimicry in butterflies in the mid-19th century, a great many plants and animals have been found to be mimetic. In many cases the organisms involved belong to the same class, order, or even family, but numerous instances are known of plants mimicking animals and vice versa. Although the best-known examples of mimicry involve similarity of appearance, investigations have disclosed fascinating cases in which the resemblance involves sound, smell, behaviour, and even biochemistry.

Credit : Britannica 

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Titmouse, also called tit, plural titmice, small cheery-voiced nonmigratory woodland bird. Along with the chickadees, titmice make up the family Paridae (order Passeriformes), with approximately 55 species throughout the world, mostly in the Northern Hemisphere.

Bold and athletic, the titmice are among the best-loved visitors to bird feeders. Although they range in size from 11.5 to 20 cm (4.5 to 8 inches), most fall in the middle of this range (17 cm [6.5 inches]). Despite their small size, they are extremely athletic and hardy. Many live in the far north and are able to endure bitterly cold winters, in part thanks to their strategy of storing food in bark crevices or holes and remembering the locations for later retrieval. Special leg muscles enable them to hang upside down to feed, allowing them to feast on items such as insect eggs that might be missed by less-agile birds.

Of the 10 North American species, the tufted titmouse (Baeolophus bicolor, formerly Parus bicolor) is the best known, ranging widely over the eastern United States, where its cheery whistled “peter-peter-peter” rings through deciduous woodlands, orchards, and suburbs. Often attracted to bird feeders, this handsome crested little bird relishes sunflowers, although insects make up two-thirds of its diet. Caterpillars are important prey in summer. Five to nine eggs are laid in a hollow tree lined with soft materials that may include hair plucked live from startled woodchucks, dogs, or humans. One of the offspring from the previous year may assist parents in raising the spring’s nestlings. The presence of winter bird feeders has helped the tufted titmouse increase its range into southern Canada.

In Europe and Asia, the blue tit (Cyanistes caeruleus), with its light yellow belly and bluish wings, is an equally popular visitor to bird feeders, where it is renowned for its agility. Of all the birds that feed their own young, this species lays the largest clutch in the world; it can lay as many as 15 eggs. In woodlands, blue tits are often seen feeding with other tits, such as the great tit (Parus major). This widespread, adaptable species is found from Great Britain through Russia to Japan and southern Asia. It is a common visitor to backyards and lays its eggs in drainpipes, mailboxes, and hollow trees.

Credit : Britannica 

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Roosting, or resting in trees, is common, especially during the non-breeding season. It seems that all American Robins gather in roosting communities in the winter, the adult males roost in the breeding season, the females after nesting is completed, and the young birds as soon as they can make the trip to the roosting area. Robin roosts can include as many as 250 000 birds, but they usually contain from 20 to 200 birds. Sometimes American Robins roost with other species, like European Starlings and Common Grackles. Roosting seems to be a way to protect against predators and to locate feeding areas, especially in winter, when the roosting groups travel about in search of food.

The American Robin has an extendible esophagus, or canal between the mouth and the stomach. This can be useful in winter, for example, when the bird may store fruits in the esophagus before it settles for the night. This probably allows the robin to survive low nighttime temperatures.

The American Robin was originally a forest species, but it has adapted well to residential areas, where it feeds on lawns and nests in gardens and city parks. As trees have been planted, it has invaded the prairies, and it is often found in alpine forests and meadows above the treeline, so that there is scarcely any type of habitat, except marshes, where the American Robin will not nest. It prefers to winter in open areas, but does live in pinewoods and orange groves.

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The story about Benjamin Franklin wanting the National Bird to be a turkey is just a myth. This false story began as a result of a letter Franklin wrote to his daughter criticizing the original eagle design for the Great Seal, saying that it looked more like a turkey. In the letter, Franklin wrote that the “Bald Eagle...is a Bird of bad moral Character. He does not get his Living honestly…[he] is too lazy to fish for himself.”

About the turkey, Franklin wrote that in comparison to the bald eagle, the turkey is “a much more respectable Bird, and withal a true original Native of America...He is besides, though a little vain & silly, a Bird of Courage.” So although Benjamin Franklin defended the honor of the turkey against the bald eagle, he did not propose its becoming one of America’s most important symbols.

The story that Franklin proposed the turkey as the national symbol began to circulate in American newspapers around the time of the country’s centennial and are based on a January 26, 1784, letter in which he panned the eagle and extolled the virtues of the gobbler to his daughter, Sarah. In doing so, though, he was not delivering a critique of the Great Seal but a new medal issued by the Society of the Cincinnati, an association of Continental Army veterans. “For my own part I wish the bald eagle had not been chosen as the representative of our country,” he wrote. The Founding Father argued that the eagle was “a bird of bad moral character” that “does not get his living honestly” because it steals food from the fishing hawk and is “too lazy to fish for himself.”

In contrast, Franklin called the turkey “a much more respectable bird” and “a true original native of America.” While he considered the eagle “a rank coward,” Franklin believed the turkey to be “a bird of courage” that “would not hesitate to attack a grenadier of the British Guards who should presume to invade his farm yard with a red coat on.” While the private letter was a spirited promotion of the turkey over the eagle, Franklin never made his views public, and when the chance had been given to him to officially propose a symbol for the United States eight years earlier, his idea was biblical, not avian.

Credit : History

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