Where did they come from? Evolution of Birds 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 Elephant bird weighed ~1000 pounds 2 gallon eggs

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