•Started relatively late
•requires significant modifications:
•Warm- blooded animals
What are three levels of Flight?
•body surface increases to provide resistance to air
•take advantage to air movement
When was air space conquered?
•Devonian-395 million years ago
•Animals and plants moved on land
•First spores used air space for distribution
Why do some dinosaurs fly?
•Larger distance in shorter time
•Arctic Tern with an annual migration route of 30000 Km
•Discovery of new areas, inaccessible over land-colonization by air
•formation of new islands
•more vegetation animals are able to fly over there
•predators can be escaped
•Flyers can escape predators
•predators can capture their prey
•Almost every group of vertebrate has members with the ability to:
Lizards & Geckos
•Membranes along the side of body
•Draco volans, a flying lizard from southeast Asia
•Ribs extend beyond body
•Air born for about 15 m
•From Southeat Asia, India, and Sri Lanka
•Flattens its body to increase air resistance
•Bats, flying squirrels & flying lemurs
•Fossil record goes back 60 million years
•Fossil record of 60 million years
•Four greatly elongated fingers
•Flying reptiles have one finger
•Birds have feathers instead
•Appeared at the end ofTriassic
•213 Million years ago
Since late Jurassic
recent finds in texas place origin of birds back to time of pterosaurs
What do flyers have in common ?
•Hollow bones for body weight reduction
•Some fused joints to reduce flexibility for controlled movement
•Warm-bloodedness for constant high levels of energy
•cut open bone shows hollow spaces, some solidity
•If its not buried rapidly it will not fossilize nicely
Poor fossil record of flyers
•Hollow and fragile bones
•Poor fossilization potential
•Lithographic limestones of Solnhofen offers preservation potential
•Chalks of Kansas
•Geological time when we had chalk deposits?
•Cretaceous time when we had interior seaway.
•what kinds of environment?
•What was chalk made of?
Solnhofen - Germany
•140 Mil. years (Jurassic) central Europe was covered by a tropical sea
•Quiet lagoon sheltered by barrier reef
•Carbonate factories (precipitation) allows for forming carbonate sand and mud
and the animals that fall in there are well preserved.
•Reef builders: sponges, corals.
•In these sediments you find fossils.
•What is the environmental factor in these lagoons?