New Family Tree Illuminates 'Big Bang' in Bird Evolution After Dinosaur Extinction

Comprehensive look at bird genes shows power of DNA to answer a staggering array of scientific questions.

A massive genetics project has produced the most comprehensive bird family tree ever, an embarrassment of scientific riches for studying everything from how birds evolved so quickly after dinosaurs disappeared to the ways in which birds and people learn.

Researchers mapped the complete set of DNA instructions, or genomes, of 45 bird species representing every group of living birds, as well as representatives of all three groups of crocodilians—the closest living bird relatives. To produce the new family tree, scientists combined this information with previously published sequences for zebra finches and domestic turkeys and chickens.

Most of our notions of how DNA evolves over time come from studying the genetic instruction books of mammals, says Ed Green, a genome scientist at the University of California, Santa Cruz.

Adding the genomes of birds and crocodilians—the American alligator, saltwater crocodile, and Indian gharial—now allows scientists to better understand how these groups are related, he says.

The new study finds the rate of change in birds' DNA took off 66 million years ago when most dinosaurs went extinct. The surviving dinosaurs then radiated into a constellation of species that led to about 95 percent of birds on the planet today, says Erich Jarvis, a neurobiologist at Duke University in Durham, North Carolina. (See how "Birds Evolved From Dinosaurs Slowly—Then Took Off.")

The biggest takeaway from the eight studies published Thursday in the journal Science is the way genetic codes can be used to answer wide-ranging questions. Scientists are using birds' DNA, for instance, both for research on the brain and learning and to reconstruct what an ancient ancestor of birds and dinosaurs might have looked like.

Hi!

hello frnds today we talking about some special about animal and it is  LIGER!!!!

Who is that one want to know O.K. Let see....................

           The liger is a hybrid cross between a male lion (Panthera leo) and a tigress (Panthera tigris). Thus, it has parents with the samegenus but of different species. It is distinct from the similar hybrid tiglon. It is the largest of all known extant felines.

Ligers enjoy swimming, which is a characteristic of tigers, and are very sociable like lions. Ligers exist only in captivity because the habitats of the parental species do not overlap in the wild. Historically, when the Asiatic Lion was prolific, the territories of lions and tigers did overlap and there are legends of ligers existing in the wild. Notably, ligers typically grow larger than either parent species, unlike tiglons which tend to be about as large as a female tiger.

LIGER COUPLE.

The history of ligers dates to at least the early 19th century in India (Asia). In 1798, Étienne Geoffroy Saint-Hilaire (1772–1844) made a colour plate of the offspring of a lion and a tiger.

In 1825, G. B. Whittaker made an engraving of liger cubs born in 1824. The parents and their three liger offspring are also depicted with their trainer in a 19th century painting in the naïve style.

Two liger cubs born in 1837 were exhibited to King William IV and to his successor Queen Victoria. On 14 December 1900 and on 31 May 1901, Carl Hagenbeck wrote to zoologistJames Cossar Ewart with details and photographs of ligers born at the Hagenbeck's Tierpark in Hamburg in 1897.

In Animal Life and the World of Nature (1902–1903), A.H. Bryden described Hagenbeck's "lion-tiger" hybrids:

        It has remained for one of the most enterprising collectors and naturalists of our time, Mr. Carl Hagenbeck, not only to breed, but to bring successfully to a healthy maturity, specimens of this rare alliance between those two great and formidable felidae, the lion and tiger. The illustrations will indicate sufficiently how fortunate Mr. Hagenbeck has been in his efforts to produce these hybrids. The oldest and biggest of the animals shown is a hybrid born on the 11th May, 1897.

        This fine beast, now more than five years old, equals and even excels in his proportions a well-grown lion, measuring as he does from nose tip to tail 10 ft 2 inches in length, and standing only three inches less than 4 ft at the shoulder. A good big lion will weigh about 400 lb [...] the hybrid in question, weighing as it does no less than 467 lb, is certainly the superior of the most well-grown lions, whether wild-bred or born in a menagerie.

        This animal shows faint striping and mottling, and, in its characteristics, exhibits strong traces of both its parents. It has a somewhat lion-like head, and the tail is more like that of a lion than of a tiger. On the other hand, it has no trace of mane. It is a huge and very powerful beast.