where did they come from?

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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) - PowerPoint PPT Presentation

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Evolution of Birds:

Where did they come from?

Archaeopteryx lithographica

Archaeopteryx
Fossils known only from the Solnhofen lithographic limestone quarry in Bavariafirst discovered in 1861the perfect missing link between reptiles and birds (Origin of Species - 1859)only other specimens found in 1857, 1877, 1951, 1974 (birds dont 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

Archaeopteryxdates to the Jurassic, ~160 mybpslightly larger than a pigeondid more gliding rather than flyingclawed fingers for climbingsolid reptilian boneshad feathers and a furculaprobably not on the mainline of bird evolution

Diatryma
~60 mybplarge carnivore7 ft. tall and flightlessprobably ran down mammals and reptilesfound in New Jersey (as well as elsewhere)

Phororhacos
~30 mybpabout as tall as a manlived in South America, probably before the before large predatory mammals lived there

Elephant birdweighed ~1000 pounds2 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 Archaeopteryxmore birdlike, more advancedperhaps more on the evolutionary mainstream of birdsgives stronger evidence to dinosaur lineage