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)
Why were jaws important to vertebrate evolution?
Enabled animals to become more efficient predators and adapt to a wider range of ecological niches.
What were the early predators of fish?
Arthropods (like sea scorpions)
Major groups of bony fish are divided into two major groups:
- Ray-Finned (angelfish, tunafish)
- Lobe-Finned (uncommon today)
What type of “finned” fish does this describe?
- Looks very fragile, fins are made of skinny bones
- Useful for swimming
- Usually can’t support the weight of the fish on land
Ray-Finned Fish
What type of “finned” fish does this describe?
- Fins are muscular, with thick bones
- Still has rays
- Don’t live in many parts of the world
- Walking like swimming motion is useful on land
Lobe Finned Fish
What type of lobe-finned fish does this describe?
- Breathe air
- Live in Amazon rainforest
- Have lungs– can come up to surface and come up for fresh air
- Spend whole life in water, just come up to surface for air
Lungfish
What are lobe-finned fish? What important features do they share with land animals?
- Fish that walk and breathe air
- Have many bones and muscles in their fins, useful for supporting the body on land, as in lungfish and tetrapods; had lungs along with gills, which allowed them to breathe air.
In what period is there vertebrate life on land?
Devonian period
Why would a fish breathe air?
So they can survive briefly on land; warm water doesn’t hold much oxygen, so some fish living in warm ponds find a solution by popping out into the surface to get a boost of oxygen (ex: gars do this)
vertebrates with four limbs instead of fins
tetrapods
T or F: limbs and lobe fins share homology
True
What evidence shows that early tetrapods like Tiktaalik were beginning to move on land?
Tiktaalik has four leg-like fins, which is similar to amphibians, suggesting that early tetrapods were beginning to move on land.
What was the first fish to live on land; first land vertebrates
tiktaalik
water-breathing young (tadpoles) turn into land-living adults
amphibians
How are amphibians connected to aquatic life and to life on land?
When young, they have to live in water and breathe (using gills) and when they grow, they grow lungs and legs. They need water to lay their eggs (ex: frogs, toads, salamanders)
What are the two reasons why amphibians would live in water and then leave to move onto land?
- Potential food sources
- Possible places to hide from predators
What was the first living THING on land?
Plants
How were early land plants in the mid-Paleozoic different from plants today?
- Early land plants consist of spores (seedless)
- Plants today: seed-producing plants; plants with flowers and seeds
What’s a similarity between amphibians and the early land plants?
They need water to reproduce (amphibians: lay their eggs in water; plants: spores need wet soil)
T or F: When early tetrapods are coming out, there are already forests.
True
Where were early forests located?
In wet swamps
What kind of environment did early land plants live in? What kind of sedimentary rocks form in that environment, and how is it important to the modern economy?
- Wet, swampy areas
- Coal
- Coal is important to the modern economy because it’s burned for electricity
What is the “equation” to make coal?
- Dead plants (most important ingredient) + heat + pressure
- Dead plants have to be buried (which creates heat and pressure) to go through the changes that make coal.
What period is the oldest coal found from?
Devonian
What period is considered the “Coal Age”? Why?
Pennsylvanian; the largest amounts of coal were created during this time
How did the climate change as North America became part of Pangea? What evidence for this change can we see in the rocks?
- Sea level change, shifts in oceanic chemistry, development of new ecosystems.
- We can see that the sea level changed because metamorphic rocks started out as ocean sedimentary rocks, which means they were underwater before the continents collided. Fossilized plants during this time show how the climate changed.
T or F: Appalachian Mountains was going through weathering and erosion, which created coal. Used to be much bigger back in Pennsylvanian times.
True
What direction was North America moving in the Pennsylvanian period (paleozoic era)?
East
Which describes the Appalachians in the Pennsylvanian and which describes the Appalachian Mountains today?
1. the highest part of the mountains and the middle of the mountains was far east.
2. flat to the west, up and down in the middle, goes downhill towards the ocean very gently in the east.
- appalachians then
- appalachians now
In Chewacla State Park, you can find metamorphic rock called _____.
gneiss
What is the most famous metamorphic rock in our state?
Marble (metamorphosed limestone)
The ______ plateau in Alabama is the plateau region of the App. Mountains in Alabama.
Cumberland
Paleozoic Continental Collisions:
What collision happened during each o f these periods?
1. Ordovician
2. Devonian
3. Pennsylvanian
- Ordovician: taconic orogeny
- Devonian: acadian orogeny
- Pennsylvanian: alleghanian orogeny
What is an orogeny? What is the name of the orogeny that produced the Appalachian Mountains?
- Orogeny: any event that makes mountains
- Alleghanian Orogeny
a type of egg that contains a fluid-filled sac, which surrounds the embryo and provides protection and nourishment.
amniotic egg
Why is an amniotic egg important for animals that live on land (2 things)?
- Allowed animals to reproduce on land, away from a water source
- Allowed them to colonize a variety of habitats that were previously unavailable
What are the three geological regions of the Appalachian Mountains? How do they provide evidence for a convergent boundary there during the Paleozoic?
- Piedmont: metamorphic rocks where the continents collided
- Valley and Ridge: layered sedimentary rocks (folds and faults in these rocks; broken under pressure, not heated up)
- Plateau: horizontal (flat) sedimentary layers (this area didn’t experience much pressure at all)
What is the name of the supercontinent that formed during the Paleozoic Era?
Pangea
a big landmass of continents together
supercontinent
