Exam 3: Part 1 Flashcards
What is the first period of the Paleozoic era?
The Paleozoic Era begins with the Cambrian period
When did the Phanerozoic eon begin?
The Phanerozoic Eon begins with the Paleozoic era
the age of (complex) animals
Phanerozoic eon
the rapid appearance of complex animal life; large increase in the diversity of life; includes first members of most animal phyla
Cambrian Explosion
Why is the Cambrian Explosion important (2 things)?
- It was the time of the first known predators, creating an animal food chain.
- During the Cambrian Explosion, most major animal groups (phyla) first appear (different species, but same basic body structures)
Why is the Paleozoic era important? (3 things)
- Major biological events
- Energy resources (coal, oil, and natural gas)
- Shaping the North American landscape (Appalachian Mountains)
What preserved hard AND soft parts from an ocean environment and thousands of Cambrian species are preserved there (ex: the “party” worm)?
Burgess Shale
In order to preserve soft parts at the Burgess Shale, what had to be true about burial?
There had to be fast burial with very little oxygen
What was different about living things from the Cambrian onward that made them more likely to become fossils compared to Precambrian life?
The rise of animals with hard shells meant that they had a much better chance of becoming fossilized. (Had hard shells to protect from predators)
How is the Cambrian food chain different from that of the Ediacara biota? How can we tell?
- Edicara biota= no predators, so no food chain.
- Cambrian= food chain actually exists; there were first known predators during the Cambrian, creating an animal food chain.
- Direct Evidence: there are trace fossils from the Cambrian period that have bites taken out of them.
What is one of the most important groups of living things on the planet from the Paleozoic era?
Fish
What ARE fish?
Things with fins and gills (not like starfish)
T or F: There is a great diversity of fossil fish that can tell us about life in the ancient ocean and on land.
True
What phylum do humans belong to?
Phylum Chordata
have a stiff support down the back (a mineral backbone or a non-mineral notochord).
chordates
T or F: Not all chordates have a backbone; some have a notochord which is in the same location in the body from the head to tail.
True
What animal does this describe from the Cambrian period:
- Built like the modern amphioxus
- ______ and similar early chordates are important for our existence (and anything with a backbone) because if they had a mass extinction that would affect the existence of anything with a backbone today.
Pikaia
chordates with backbones
vertebrates
The skeleton is made of bone, which is made of _____ _____.
calcium phosphate
When do vertebrates show up?
After the Cambrian period
What are four examples of vertebrates?
- Humans
- Dogs
- Cats
- Fish
T or F: All vertebrates start with a notochord, and the bone grows around it, then the notochord dissolves and the bone replaces it.
True
What outnumbers all the other vertebrates combined? How many species are there?
Fish; 30,000
What periods are considered the “Age of Fish”
Ordovician, Silurian, Devonian (early Paleozoic era)
What features of the earliest fish make them different from the animals that came before?
The earliest known fish did not have jaws; later on we see them develop jaws, backbones and skeletons
What is one big difference between early Paleozoic fish and modern fish?
Early Paleozoic fish did not have jaws or teeth. (limits the ability for it to eat certain foods)