dinosaurs

Archaeopteryx

A 150-million-year-old fossil that provided evidence for the transition from reptiles to birds, exhibiting both bird-like and reptilian features.

Deinonychus

A theropod dinosaur whose claw discovery suggested that some dinosaurs were fast and warm-blooded, linking them closer to birds.

Feathers

Evolved before flight in theropods, initially serving purposes like insulation or communication before being adapted for flight.

Saurischian

A classification of dinosaurs characterized by a backward-facing ischium and includes theropods and sauropods.

Ornithischian

A classification of dinosaurs characterized by backward-facing ischium and pubis; they were all plant-eaters.

K-T Extinction Event

A mass extinction event occurring 66 million years ago, marking the end of the Mesozoic Era and leading to the rise of mammals.

Luis Alvarez's Hypothesis

Proposed that high iridium levels found at the K-T boundary were linked to an asteroid impact, causing a mass extinction.

Chicxulub crater

The impact site on the Yucatan Peninsula associated with the asteroid believed to have caused the K-T extinction event.

Theropods

A group of bipedal, primarily carnivorous dinosaurs that exhibit many skeletal features resembling those of birds.

Exaptation

The process by which a trait evolves for one purpose and is later adapted for another purpose, such as feathers evolving for insulation before flight.

Iridium

A rare element found in high levels at the K-T boundary clay layer, supporting the asteroid impact theory for the mass extinction.

Fossil evidence of dinosaur nesting

Discoveries of nesting grounds that showed parental care in dinosaurs, indicating behaviors similar to modern birds.

Tsunamis and tektites

Geological evidence supporting the asteroid impact theory, indicating massive disturbances from an oceanic impact.

Burrowing animals

Smaller animal species that had a higher chance of survival after the K-T extinction due to their ability to find refuge from impacts.

Evolution of primates

Resulted from the diversification of mammals following the extinction of non-avian dinosaurs, significant in the development of modern humans.