My Science School

Birds-of-paradise found in New Guinea and surrounding islands are the most attractive birds in the world. They stand out for their striking colours and bright plumage in shades of scarlet, blue, yellow and green. Males have vibrant ruffs of long, pointed feathers known as wires. Their dances are a treat to the eye.

Consider the efforts of the male Superb bird-of-paradise. He totally changes his appearance to get the attention of a female. He fans out his black feathers with a few electric-blue feathers sticking out. It makes him look a crazed smiley face. Then he hops around excitedly, making sure the female always gets his best angle. He whirs and clicks and snaps his tail in rhythm, flashing a breastplate of shimmery feathers. The female watches, showing no emotion.

His dance moves may appear unpredictable, but they are carefully planned. He is trying to convince a female that he is the best mate. The male works hard to impress, tirelessly refining his moves until the female is won over. After all, she is the one in control. She ultimately decides who her mate will be.

Stunning as it is, the male's beauty is impractical. For example, take the ribbon-tailed Astrapia. It boasts bright white tail feathers that stretch one meter (three feet) long. Such long tail feathers might help it attract mates, but they aren't exactly useful for survival.

So how did long feathers and other features evolve? Famous naturalist Charles Darwin proposed his theory of natural selection to answer the question of how certain animals end up with certain features. Natural selection is sometimes called "survival of the fittest." It means that animals with traits that help them survive will live on. A trait might be its color. It might be what they eat or how they hunt. If an animal lives long enough, its children can also have traits that help them survive. Animals without these traits might get eaten or die out.

Yet the Astrapia's trait of bright long tail feathers does not seem to offer any survival advantage. They actually might put the bird at risk. A predator could spot it easier.

Credit : National Geographic Society

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The cassowary is considered the most dangerous bird in the world. The large, flightless bird, native to Australia and south-east Asia, has 4-inch long, dagger-like claws. It can inflict injuries with slashing blows of its feet. Besides, it has a reputation for aggressively defending itself when threatened.

Cassowaries are certainly striking to look at, with a vivid blue face, two red wattles (flaps of skin) hanging from their neck and a hollow "helmet", known as a casque, atop their heads. 

The anatomy that makes them so dangerous lies lower down. Muscular legs that can pack a powerful kick terminate with three claw-tipped toes. The claw on the inner toe is particularly formidable, reaching lengths of 12 cm (5 in)! If a cassowary feels threatened, it will leap up and strike out with these dagger-like weapons, inflicting potentially lethal wounds to internal organs and causing severe bleeding. 

Although this avian family are widely considered the most dangerous birds, this is the first confirmed human death attributed to a cassowary in 93 years. The last-known victim was 16-year-old hunter Phillip McClean, who tripped while fleeing from a bird in Australia in April 1926. It was when McClean was on the ground that he received a fatal blow to the neck. 

Credit : Guinness World Records

Picture Credit : Google

Oxpecker is a bird that belongs to the family Buphagidae, and found only in Sub-Saharan Africa.

It inhabits open savannah and grassy plains. It has a light brown plumage. Depending on the colour of my bill, it is either a yellowbilled oxpecker, or a red-billed oxpecker.

It feeds on tick, flies, lice, and worms that are found on the bodies of cattle, rhinos, giraffes, and large antelopes. Though, in a way, it cleans the body of the cattle. It is known as a parasite because it also feed on the blood of the host. It is a social bird. It whistles and makes chattering sounds to communicate.

Oxpecker/mammal interactions are the subject of some debate and ongoing research. They were originally thought to be an example of mutualism, but recent evidence suggests that oxpeckers may be parasites instead. Oxpeckers do eat ticks, but often the ticks that have already fed on the ungulate host and there has been no proven statistically significant link between oxpecker presence and reduced ectoparasite load . However one study of impalas found that impalas which were used by oxpeckers spent less time grooming themselves suggesting they had fewer parasites. Oxpeckers have been seen opening new wounds and worsening existing ones in order to drink the blood of their perches. Oxpeckers also feed on the earwax and dandruffs of mammals, although less is known about the benefits of this to the mammal, it is suspected that this is also a parasitic behaviour. Some oxpecker hosts are intolerant of their presence. Elephants and some antelope will actively dislodge the oxpeckers when they land. 

Picture Credit : Google

The wandering albatross, which is adept at gliding, has the largest wingspan of any bird in the world, reaching up to 3.5 metres or 11 feet. Weighing between 17 and 25 pounds, this seabird can travel long distances for years without touching land. The species is known to circumnavigate the Southern Ocean thrice each year.

These frequent fliers are known for spending months in the air without touching down, as well as having some unique mating arrangements. However, thanks to harmful fishing techniques and predation by invasive species, albatrosses around the world are either under threat or endangered.

There are 23 species of albatrosses, though arguably the most famous is the wandering albatross (Diomedea exulans), which is the largest flying bird in the world. This bird has a 11-foot (3.4 meter) wingspan, according to the Encyclopedia Britannica — even bigger than the famous California condor — and it uses those massive flappers to travel thousands of miles in a single journey.

Credit : Live Science 

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Blue jay is a songbird that belongs to the family of crows, and found in Central and Eastern parts of North America and South Canada.

Its face, throat and belly are white, while wings and tail are covered with white, black and blue plumage. It has a crest on top of the head.

It is known for being highly adaptable and intelligent. It makes an excellent imitation of several hawk calls to check if there are any hawks in the area.

It is an omnivore, eating seed, nuts, acorns, fruit, insects, eggs and young birds. Hawks, owls and cats prey on adult birds, while snakes, raccoons, squirrels, opossums and crows attack young birds and eggs.

This is a rare characteristic among birds, and it is called sexual monomorphism, meaning the males and females look the same. Other species of birds have males and females that look very different, which is called sexual dimorphism. With male and female Blue Jays having similar plumage, it’s difficult to tell them apart. However, male Blue Jays are slightly larger.

Seven US states claim the Northern Cardinal as their state bird, but the Blue Jay is not recognized as a state bird in any US state. However, they are the mascot of a Major League Baseball Team, the Toronto Blue Jays.

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The blue penguin, also little penguin or fairy penguin is the smallest of all known penguin species. Found on the coastlines of southern Australia and New Zealand, it grows to an average height of 33 cm and weighs no more than a kg.

Although the length of the breeding season varies by subspecies and geography, it generally occurs between June and December. Breeding pairs tend to nest in hidden areas that are relatively free of mammalian predators—such as on cliff crevices, in ground burrows, in caves, or under vegetation. Compared with other penguin species, most blue penguins are monogamous; pair breakups are uncommon, occurring only after unsuccessful nesting attempts. Breeding pairs also tend to return to the same nests year after year, and some pairs occupy the same nest year-round.

If mating is successful, a clutch of two eggs is produced. Each parent takes a turn incubating the eggs, while the other returns to sea to feed. This pattern continues after the eggs hatch some 35–37 days later, at which point the parents take turns supplying the chicks with food. The parents also take turns guarding the chicks until the chicks are 18–38 days old. Unlike other penguin species, however, older blue penguin chicks tend to remain in the nest during the day when both parents are out hunting. In general, they do not form “crèches” (groups) with chicks from other nests; however, some studies note that crèches may form among blue penguin chicks that nest in large caves. Fledging, the stage in which the young transition to adulthood, takes place when the chicks are between 50 and 65 days old. During this stage, the young forage in the sea for the first time. Although some may leave the nest during this period, most will remain with their parents before becoming fully independent a few weeks later. Most males and females reach sexual maturity at age three. While the life span of the blue penguin is generally six to seven years, some studies note that a few individuals can live as long as 25 years in the wild.

Credit : Britannica 

Picture Credit : Google

Whistling Kites got their name as they produce a distinctive, descending whistling call, commonly followed by a quick succession of higher-pitched notes.

Whistling Kites are medium-sized raptors (birds of prey) that have pale buff upperparts and heads. The wings are dark-ish brown and flight feathers black. Under the wings, there is a characteristic 'M' shape that becomes apparent whilst open and in flight. Underparts are slightly lighter than the uppers. Their general appearance is often described by many as being 'shaggy'.

Both the head and body are quite slender. Relative to size, both the wings and rounded tails are considered long. The legs of these raptors are short, but this doesn't affect their ability to walk on the ground. Legs are featherless and bone coloured, as are the feet. Eyes are black, and the beak is grey-ish, short, sharp and curved.

Credit : Bird Fact

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A keystone species is one that has an incredibly important role to play in an ecosystem. Without this species, ecosystem would be dramatically different or may even stop existing altogether. It can be any organism, from large animals to microscopic bacteria. In short, a keystone species is what holds a habitat together.

There's a call to protect the tiger because as a keystone species, this top predator plays a significant role in the health and diversity of an ecosystem.

If it disappears, the population of its prey - usually ungulates - will go up, and this will result in the decimation of vegetation, leading to a collapse of the ecosystem.

Not just animals, birds and insects, even plants can be keystone species.

Mangroves are a keystone species that firm up shorelines and reduce erosion. They provide a safe haven and feeding area for small fish among their roots, which reach down through the shallow water.

It is true that if bees go extinct, so would humans. This keystone species plays a very important role in keeping the world going.

As the most important pollinators, they are responsible for about a third of the world's total food production. Without bees, there would be food shortage, and eventual human collapse.

Picture Credit : Google

The Antpitta avis canis Ridgley is a bird that barks like a dog. The nearly-flightless insect eater has long bluish legs, a grey belly and brown back, and its black head bears a prominent white patch across the face. Discovered by ornithologist Robert S. Ridgley in the Andes in Ecuador in June 1998, the bird is the size of a duck, and is one of the largest birds discovered in the 20th century.

Thirty of these long-legged, black-and-white barking birds were found. It apparently had gone undetected because it lives in remote parts and, of course, doesn’t sing. The size of a duck, it is one of the largest birds discovered in the last 50 years.

There are also dogs that do not bark! The basenji, smallish dog with a silky copper coat, does not bark. Instead, it yodels when it gets excited. Wild dogs like the African Wild Dog also do not bark.

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