Term List #2 - Biol 3p03 Flashcards
Ammonoidea
extinct, coiled-shelled cephalopods . They are more closely related to living octopuses, squid, and cuttlefish than they are to nautiluses
what is the different between ammonoidea and nautiloidea
Ammonoidea has more suture complexity than Nautiloidea which allows them to be stronger, as there is more welding holding the valves together. ammonoidea is also exinct whereas nautiloidea is not
Archeocyatha
‘ancient cups’ is a taxon of extinct, sessile, reef-building marine sponges that lived in warm tropical and subtropical waters during the Cambrian Period
belemnite
an extinct cephalopod mollusk with a bullet-shaped internal shell that is typically found as a fossil in marine deposits of the Jurassic and Cretaceous periods
Bivalvia
Bivalves are aquatic, invertebrate animals that have 2 shells of equal size they can close around themselves. They can be found in salt, fresh, and brackish water.
Cambrian Fauna
the unique assemblage of marine animals that emerged during the Cambrian explosion, a period of rapid diversification of life around 540 million years ago, characterized by the appearance of hard-shelled organisms like trilobites and other invertebrates.
Cephalopoda
meaning “head-foot” in Greek, refers to a class of marine mollusks including octopuses, squid, cuttlefish, and nautilus, characterized by a prominent head, highly developed eyes, and arms or tentacles modified from the primitive molluscan foot.
ceratitic
an extinct genus of ammonite cephalopods. These nektonic carnivores lived in marine habitats in what is now Europe, during the Triassic, from the upper-most Anisian to the lower Ladinian age.
convergence
the tendency of unrelated animals and plants to evolve superficially similar characteristics under similar environmental conditions.
Coleoidea
one of the two subclasses of cephalopods containing all the various taxa popularly thought of as “soft-bodied” or “shell-less”
Cope’s Rule
named after the paleontologist Edward Drinker Cope, describes the evolutionary trend where lineages tend to increase in body size over time.
Court Jester Hypothesis
large-scale evolutionary changes, including speciation and extinction, are primarily driven by abiotic factors like climate change and geological events, rather than biotic interactions
Devonian Nekton Revolution
a period of rapid diversification and expansion of actively swimming (nektonic) animals, particularly fish, during the Devonian Period (roughly 419 to 359 million years ago).
Divergence
the process where a population of an ancestral species evolves into two or more descendant species, becoming increasingly dissimilar in form and structure due to adaptation to different environments or selective pressures.
evolutionary trends
identifiable, long-term patterns of directional change in the overall evolution of a trait within a group of organisms, representing a persistent direction of evolution
functional morphology
the study of the relationship between an organism’s structure (form) and its function, analyzing how anatomical features are adapted to specific behaviors and ecological contexts.
Gastropoda
a large class of mollusks which includes snails, slugs, whelks, and all terrestrial kinds. They have a large muscular foot for movement and (in many kinds) a single asymmetrical spiral shell
giantism
The evolutionary trend in which a species develops significantly larger body sizes compared to its smaller-bodied ancestors, often as an adaptive response to ecological pressures such as predation, resource availability, or environmental conditions.
goniatitic
ammonoid cephalopods that form the order Goniatitida, derived from the more primitive Agoniatitida during the Middle Devonian some 390 million years ago
Great Ordovician Radiation
a period of intense diversification of marine animal life that occurred during the Ordovician period (roughly 485.4 to 443.4 million years ago
HAM
Human and other Animal Morphology”, a field that studies the morphology and anatomy of extinct animals, including humans and their ancestors, through the analysis of fossilized remains.
homology
two or more species having structures of the same embryonic origin
Hox genes
a group of related genes that encode transcription factors. play a major role in determining body plan of an embryo
ichnofossil
a fossil of a footprint, trail, burrow, or other trace of an animal rather than of the animal itself. (trace fossil)