where did they come from?

Where did they come from?

Archaeopteryx lithographica

Archaeopteryx•Fossils known only from the Solnhofen lithographic limestone quarry in Bavaria

•first discovered in 1861

•the perfect ‘missing link’ between reptiles and birds

• (Origin of Species - 1859)

•only other specimens found in 1857, 1877, 1951, 1974 (birds don’t fossilize well . . .why?)

•the most important and valuable fossil known

What was Solnhofen like then?

Solnhofen Quarry now

A feather!

•probably for thermoregulation rather than flight

Archaeopteryx•dates to the Jurassic, ~160 mybp

•slightly larger than a pigeon

•did more gliding rather than flying

•clawed ‘fingers’ for climbing

•solid reptilian bones

•had feathers and a furcula

•probably not on the mainline of bird evolution

Diatryma

• ~60 mybp• large carnivore• 7 ft. tall and flightless• probably ran down

mammals and reptiles• found in New Jersey

(as well as elsewhere)

Phororhacos

• ~30 mybp• about as tall as a man• lived in South

America, probably before the before large predatory mammals lived there

•Elephant bird•weighed ~1000 pounds•2 gallon eggs

Aepyornis

What is the ancestral line?

Dinosaurs?

Crocodiles?

Recent research developments:

• 1984 finding of a new ‘oldest bird fossil’ from Texas, Protoavis

• ~75 my older than Archaeopteryx• more birdlike, more advanced• perhaps more on the evolutionary mainstream of

birds• gives stronger evidence to dinosaur lineage• and there’s more . . .

Feathered Dinosaurs Found! Two species of dinosaur have recently been found in northeast China which possess feathers (Qiang et al. 1998). Protoarchaeopteryx robusta and Caudipteryx zoui show remiges, rectrices and plumulaceous feather impressions. Further, they are not birds, lacking a reverted (backwards facing) big toe (see number 2 below) and a quadrratojugal squamosal contact, having a quadrojugal joined to the quatrate by a ligament and a reduced or absent process of the ishium. These and other characters group Protoarchaeopteryx and Caudipteryx with maniraptoran coelurosaurs rather than birds. This fossil of Caudipteryx reveals an animal with the features of a theropod dinosaur, but with feathers over its body, which supports the idea of birds arising from dinosaurs.