Evolution of a Mythic Creature

DRAGONS!

Ancestry• Related to modern reptiles (dinosaurs, modern

alligators and crocodiles)

Phylogenetic Tree

Common Lizard Ancestor

Modern Lizards

Dinosaur

Dragon

Environmental Conditions

• Dragons are generally they are found in rocky or mountainous environments either at high altitudes or living near seaside cliffs

Adaptations

• Flying is achieved through specialized membranes and jumping into the windy updrafts provided by the currents.

Adaptations

• Dragons are a top predator, with sharp teeth and claws, similar to eagles.

6 limbs?

Where did the 3rd pair come from?

Homologous Structures

• Common ancestry with other reptile species is evident with leathery skin and cold blooded nature.

Komodo Dragon Skin (Type of Lizard)

Analogous Structures

• The Dragon wing is analogous to a bird wing. Both provide a flight mechanism.

Vestigial Structures• Modern Alligators have a bony structure

right behind the eyes – remnants of dragon horns

Extinction

• Top/large predators will always have a low population level as the amount of prey to needed sustain them will be correspondingly high.

• Dragons required hundreds of square miles to obtain enough prey.

• Global population was very low

Dragons

Deer

Plants

Extinction

• Ancestral dragons would gather yearly in global flights. At this time mating would happen.

Extinction

• As humans encroached further and further into their remote territories, they removed the dragon’s natural food sources and brought new ones – cattle and sheep.

• Subsequent predation (hunting) of the cattle and sheep meant the dragons became the hunted.

Extinction

Extinction

• Removal of individual dragons from the gene pool lead to increased inbreeding among the remaining dragons.

• Eventual extinction resulted from a loss of habitat, genetic weakness and human competition.

• Could you believe in dragons now?