Archaeologist Peter Vang Petersen comments that while the symbolism of the brooches is open to debate, the shape of the beaks and tail feathers confirms the brooch depictions are ravens.
But with a bit of a human nudge by asking a user to click on the beak, eye, and tail of the bird the app will provide around 90percentt accuracy, a very high rate for computer vision today.
At the genus level, characters used include the shape of the beak, wings, and tail; the degree of flattening of the tarsus (lower leg); size of the hallux; and the relative lengths of the leg bones.
Blackbirds have moderate-sized beaks and tails but different species have distinguishing marks in the plumage (yellow heads, red wings, glossy sheen etc).
A mystery sea creature – with a 'long beak' and 'furry tail' – is said to be baffling marine experts over the world after its carcass reportedly washed up on a beach along the east coast of Russia.
The show's title is a reference to being young and hopeful in a time of gloom, and it tells of the travails of a bird named Boris, a pigeon-sized puppet with a long beak and fluffy tail feathers whose puppeteer gives him a persuasive midair flutter and makes him dexterous enough to alight on the lip of a wine bottle and pick up a tied bundle by its string.
For example, beaks, wings, and tails were more prominent than eyes, feet and legs, and neck (see Fig. 6).
They have a tapered beak and a pointed tail.
She, a striking creature with a large beak and black-speckled tail; he, smaller but no less distinguished, with sprinkles of white interspersed on his right shoulder.
