Physical structures, characteristics or behaviors that allow an organism to survive and reproduce in its particular environment.
Any cephalopod mollusk of the extinct order Ammonoidea, having a coiled, chambered shell.
Describing fossilized bones that remain joined as they would have been in life.
The group of mammals that includes even-toed hoofed animals, such as camels, cattle, pigs, deer, giraffes, and hippopotamuses.
Any relatively small solar system object, composed mostly of rock, that orbits around the sun. Many of these objects orbit the sun between Mars and Jupiter. Their size can range anywhere from a few meters to almost 1000 kilometers in diameter.
Plates of dense, hair-like fibrous material (see keratin) that hang in rows from the roof of the mouth of certain whales for filter feeding purposes.
An extinct group of marine cephalopod, with a bullet-shaped internal shell, similar to the modern squid and cuttlefish.
Describing the ability to walk on the two hind legs rather than all four.
Members of the family Canidae, including living and extinct species of dogs, wolves, foxes, coyotes, etc.
An animal that eats only meat.
The remains of recently dead animals providing food for scavengers.
A group of marine invertebrate animals that includes the octopus, squid and chambered nautilus.
Plants that bear cones and have needle or scale-like leaves, mostly evergreen, such as pines, spruces, firs, etc.
Masses of branched roots that form near or above the surface of the soil in cycads.
Formed of a horny layer of skin or skin structures such as nails, hair or scales.
A marine invertebrate, usually possessing a cup-shaped body and five or more feathery tentacles. A few hundred species presently exist, but thousands of extinct species have been found in fossil form, particularly in Paleozoic Era limestones. The crinoids' distinctive skeletons make them important Paleozoic index fossils.
Normally unicellular, aquatic bacteria that manufacture their own food through photosynthesis. They are also known to be the oldest fossils ever found.
Tooth pattern featuring a very large number of small, slender teeth packed very closely together along the jaw, which make up efficient grinding surfaces.
Group of extinct hippo-like marine mammals characterized by cheek teeth consisting of groups of dentine/enamel pillars or columns.
Very light weight sedimentary rock composed of the remains of diatoms, or microscopic single-celled algae, which are very abundant in marine and fresh water.
Referring to walking on the front part of the toes or digits, with the hind part of the foot lifted off the ground; for example, as in modern cats and dogs.
A botanical term that refers to having male and female organs on different plants of the same species.
Any member of the phylum Echinodermata, a group of exclusively marine invertebrate animals including sea urchins, star fish, brittle stars, sea cucumbers, sand dollars, crinoids, etc.
Type of parasite that resides on external surface of the host organism.
The complete disappearance of a type of organism.
A large group of fossil animals found in the same location and regarded as from the same time period.
Very small, unicellular animals, mostly marine, that secrete shells of calcium carbonate or of cemented sand grains.
Remain, impression, or trace of an ancient animal or plant that has been preserved in Earth's crust and is older than about 10,000 years.
Genus (singular), Genera (plural)
A rank in classification in taxonomy above the species level; may include several related species.
A very long period of time encompassing from the formation of the Earth to the beginning of recorded history, extending over millions of years.
See Geologic Timeline.
Plants that produce seeds that are not enclosed within plant tissue; literally, a “naked seed”. Examples include pines and spruce.
Large, bipedal dinosaur with duck-like bills.
An animal that eats plants.
Feeding on plants.
Those ammonites whose shell was not spirally coiled.
A U-shaped bone in the throat located at the root of the tongue.
Produced under conditions involving intense heat, as rocks of volcanic origin or rocks crystallized from molten magma.
Describing a species which is abundant and widespread in fossil form, but confined to a specific period of geologic time, such that its presence can be used to geologically date the rocks in which it is found.
Feeding on insects.
The protein that makes up nails, hair, hooves, and horns and other such vertebrate structures.
Small, shrimp-like crustaceans, which form an important food source for filter-feeding marine mammals.