Jurassic - Cretaceous - TriassicTriassic - Cretaceous - JurassicTriassic - Jurassic - CretaceousCretaceous - Jurassic - Triassic
Triassic - Jurassic - Cretaceous
The Mesozoic Era lasted about 180 million years, and is divided into three periods, the Triassic, the Jurassic, and the Cretaceous.
The Stegosaurus lived 150 million years ago, while the T-Rex lived only 65 million years ago. Practically yesterday.
Ornithopoda means "bird feet", referring to their characteristic three-toed feet. This clade was also characterized by having no armour and the development of a horny beak.
...the study of the skin, muscle and flesh that surrounds bones....the study of everything between the time of death and when the fossil is unearthed....the study of how a dinosaur died based on fossilized evidence....the study of how the current environment differs from when the fossil was alive.
Taphonomy is the study of what happens to an organism after its death and until its discovery as a fossil.
This includes decomposition, post-mortem transport, burial, compaction, and other chemical, biologic, or physical activity which affects the remains of the organism.
Dry sandy plains so the wind can blow sediment to bury the dinosaurForests so plant roots and soil and decompose the flesh, leaving only the skeletonMountainside so the dinosaur is left in the open to become fossilizedWetlands so the dinosaur will be buried in mud which will solidify, preserving the fossil
Dinosaurs that died in wetlends such as floodplains or on riverbanks were often buried by mud during a flood. This silt and mud remained above the skeleton, allowing it fossilize. Other environments did not protect the skeleton before it turned to dust, allowed microbes to decompose the skeleton, or did not allow the fossil to be buried at all.
A piscivore is a carnivorous animal which eats primarily fish. The other diets are carnivore (meat), herbivore (plants), omnivore (both), and insectivore (insects).
A coprolite is fossilized feces. The name is derived from the Greek words κόπρος (kopros, meaning "dung") and λίθος (lithos, meaning "stone").
On two legs onlyOnly four legs onlyMainly on two legs, but sometimes on four legsMainly on four legs, but sometimes on two legs
Mainly on two legs, but sometimes on four legs
Adapted primarily for walking on two legs, but able to walk on four legs.
The fossilized remains of an aquatic animalThe rocks that are found surrounding a fossilA fossil that is found underwaterAny track or trail left behind by a living organism
A track or trail left behind by a living organism
This includes footprints and burrows.
Lines of Arrested GrowthLeg and Arm GradingsLymphatically Attached GastraliaLimbs with Additional Graviport
Lines of Arrested Growth
During winter, periods of slower growth due to reduced food supply mean fewer osteons are added to bone structures. Cyclically, this resembles tree trunks when the fossils are sliced thinly and creates rings that help determine the age at which a dinosaur died.