10/21 - 10/23 (Paleozoic INVERTEBRATES) Flashcards
Deck 4 (#2)
What was the Cambrian Explosion?
an abundance of fossils in rock came out of nowhere
What were the earliest shells.
Ediacaran faunas
Advantages of an exoskeleton are..?
protection against UV radiation / helps against drying out / allows animals to grow larger and attach muscles / protects against predators
Define Pelagic
organisms that live in the water column
One word to describe Plankton and Nekton
Floaters and swimmers
Define Benthos? What are the 5 subcategories of them?
Lives on the seafloor /// Epifauna / Epiflora /Infauna / Sessile / Mobile
One word to describe Epifauna and Epiflora?
1st - animal / 2nd - plants
Define Infauna, Sessile, and Mobile. (Benthos)
I - organisms that live under the bottom / S - organisms that stay in place / M -Organisms that . . . move
Name the 4 types of feeding. (marine)
Suspension-feeding (filter-feeders) / Herbivores / Carnivore-scavengers / Sediment-deposit feeders
Define & give an example of Suspension-feeding.
grab bits of food from water column. AKA filter-feeders. / Sponges, corals, zooplankton, and clams
Define & give an example Sediment-deposit feeders.
mud eaters / worms
An organism’s place in an ecosystem is defined by..?
where it lives and how it eats
Define Trophic Levels.
levels of food production and consumption
Define Primary Producers.
usually autotrophs (make their own food) like plants, chemosynthetic bacteria and plankton
Define Primary Consumers.
usually herbivores
Define Secondary Consumers
usually first level carnivores
Define Tertiary consumers
top-tier predators that eat lower level predators and herbivores
Describe Trilobites by Benthos & more.
Benthic, mobile, sediment-deposit feeders (some are carnivores) / 1/2 of Cambrian Fauna
Describe Brachiopods by Benthos & more.
Inarticulates - Simple, benthic, sessile filter feeders. / Still around today! /// Articulates - Benthic, sessile, filter feeding animals / had a hinge
What is the plane of symmetry to the hinge on both Brachiopods and Bivalves.
Brachiopods - perpendicular to hinge / Bivalves - Parallel to Hinge
Are clams Brachiopods or Bivalves?
Bivalves
Describe Archaeocyathids by Benthos & more.
Benthic, sessile, suspension feeders / Sponges…maybe?
Describe Sponges by Benthos & more.
Sessile, benthic, filter feeders / Maybe Archaeocyathids
Give info on Cnidaria.
Most pulled up in Cambrian / Includes true corals and jellyfish
Give info on Molluscs.
Mobile marine herbivores & carnivores (majority of snails - carnivores) / Included Gastropods (snails), Clams, and
Cephalopods
Describe Annelids by Benthos & more.
Infaunal, benthic, sediment-deposit feeders & epifaunal, benthic, filter feeders / regular segmented worms & sea-pens
Describe Crinoids ‘sea lily’ by Benthos & more.
Sessile, benthic, filter-feeders / First appear in Cambrian / Still around today! / Nick-named the ‘sea lily’ but are actually animals.
Describe Graptolites by Benthos & more.
Planktic, filter feeders / Reproduce by cloning/budding / Had saw-toothed form / Lasted until the Mississippian
What’s special about Burgess Shale Biota?
Contains exceptionally preserved soft- bodied animals /
Many forms can’t be categorized to a known phyla / Basically we still don’t know what some of these animals were #Hallucigenia
Shout out my boy Hallucigenia!
😛
Describe the Opabinia.
Extinct arthropod / head shows unusual features: 5 eyes, mouth under the head facing backwards, and clawed proboscis that prolly passed food to mouth.
Give info on Wiwaxia.
did it exist??? We not sure, its just there
Describe the Anomalocaris.
Large Cambrian and 1st Tertiary Consumer / Grew abt 1 meter / Had barbed arms, large developed eyes, and a slim, elongate profile / could move VERY fast
Describe Ordovician Marine Community
Dominated by the brachiopods, bryozoans, stromatoporoids, and corals / Huge increase in marine fauna
Describe Bryozoans by Benthos & more.
Sessile, benthic, epifaunal suspension feeders / microscopic aquatic invertebrates that built small reef complexes thru Paleozoic (corals) / ‘moss animals’ /
Give info on Stromatoporoids
type of calcareous sponge / important reef & mound builders during the Ordovician
Give info on Corals.
1st corals (wrinkly horn corals and their tabulate relatives) appear in Ordovician, and dominate reef building environment
Percentage of all species that were destroyed in Ordovician Mass Extinction? How did this extinction MAY HAVE come about?
88% / Glaciation
What are the 5 major mass extensions? What was the biggest?
Ordovician Extinction / Devonian Extinction / Permian Extinction
Triassic Extinction / Cretaceous Extinction /// Permian Extinction
Give info on Eurypterids
Arthropod class of predators / Commonly known as ‘sea scorpions’
Give info on Ammonoid Cephalopods
Evolved from simple nautiloids / Dominant predators in Devonian
Percentage of all species that were destroyed in Devonian Mass Extinction
87%
What species dominant during Mississippian?
Crinoids
Give info on Crinoids
Dominated reef structures / Turned most of Laurasia platform into semi-consolidated muds and skeletal debris
Give info on Blastoids
Smaller cousins of crinoids / Nicknamed ‘sea buds’ / last till mid-Permian / Crinoids and blastoids belong to phylum Echinodermata because of radial symmetry
Percentage of species destroyed in Permian Mass Extinction?
Approx. 95%
