Transcript LECTURE 5: Paleozoic Era: Carboniferous/Permian

LECTURE 6:
Carboniferous Pd
(Mississippian & Pennsylvanian)
360 mya- 286 mya
and Permian Period
290 mya – 248 mya
Why is it Called the Carboniferous
Period?
• Continents were clustered at the equator
Why is it Called the Carboniferous
Period?
• Swampy tropical forests covered the continents
– Seedless Tracheophytes: tall ferns, horsetails and
lycophytes dominated
Why is it Called the Carboniferous
Period?
• Latin terms: Carbo (coal)
and ferre (to bear)
• The forests are called coal
forests
• Plants that lived in these
forests 300 million years
ago became coal mined for
fuel today
– Dead plant material
accumulated and pressure
left compressed carbon—
coal—behind
What is Chicago’s Mazon Creek
Area?
• Before the Carboniferous Period, Chicago
had been an underwater reef, but during
this time it became a great forest
• This site produces some of the world’s
best fossils from the Carboniferous Period
– Plants, centipedes and millipedes, scorpions
and other arachnids, and even small
amphibians
• Some Arthropods were GIANTS
– Tully Monster (Illinois State Fossil)
• 2 meters Long Millipede
Tully Monster Tullimonstrum gregarium
Marine, Carnivore (blown ashore)
What Significant Events Occurred
During the Carboniferous?
• Radiation of Tetrapod
Diversity
• Amniotic Egg Appears
– The shell and amniotic
fluid prevent the
developing embryo
from drying out
– FIRST REPTILE
Radiation of Terrestrial
Tetrapods
• Temnospondyls Amphibiamus
– Fish-like bodies were replaced with
large predators with long snouts,
short sprawling limbs and flattened
heads
– Non-amniotic
– Layed eggs in water
• Anthracosaurs
– Reptile- Like amphibians
– non-amniote tetrapods and amniotes
with holeless skulls
– Descendents to Reptiles and
Synapsids (mammal-like reptiles)
Reptile and Synapsid Diversity
• Holes in their skull differ
• Reptiles
– One or more holes, but these holes are never located directly
behind the eye sockets
• Anapsids
– No openings
– Early Reptiles
• Diapsids
– 2 openings
– only group living today: Lizards, snakes, turtles, and crocodiles, as well
as dinosaurs and their living descendants: birds
• Synapsids
– Single opening just behind each eye socket
– The only synapsid group living today are the Therapsid
cynodonts (Mammals)
• a palate that separates the nasal passage from the mouth.
This palate allows cynodonts to breathe and chew at the same
time—something you can do that other synapsids could not do
•
What was Hylonomus lyelli ?
• First animal adapted to life fully
on land (FIRST REPTILE) 320
mya
– Anapsid
• 20 cm (8 in.) long, counting the
tail
• Lizard-like reptiles were
insectivores
• Females probably deposited
amniotic eggs on land in moist,
sheltered areas
What was Archaeothyris?
• First Mammal- Like
Reptile
What was Petrolacosaurus?
• Oldest Diapsid
Reptile
– 2 holes
What Adaptations for Land are
Seen in Early Reptiles?
• Amniotic Egg
– A yolk provides food for the developing embryo
– Moisture and oxygen are absorbed through the porous shell
– Eggs develop outside the mother's body (Oviparous)
• Dry, Scaly Skin
– The scales are thickenings of the outside layer of skin and are
mostly made of keratin
• Cold- Blooded: Ectothermic (like Amphibians)
– They depend on the environmental temperature for the warmth
that they need (low metabolism- until they are warm)
• Defense Mechanisms
– Bony shells,sharp teeth, camouflage and warning colors
What were the Significant Events
During the Permian Period?
• Supercontinent Pangaea
• Three basic environments—
arid, tropical, and
temperate
• Amniotes became common
– Reptiles and synapsids
(Therapsids- mammalian
ancestors)—spread across
the supercontinent
• Mass Extinction #3
How does Climate Affect Plant
Diversity?
• Arid (Dry)
– Zones near the equator quenched by rain in the summers, but drier the
rest of the year
• Most spore-bearing plants, such as ferns, need wet conditions for sperm to
swim to the egg. They did better nearer the equator where there was
seasonal moisture
– Zones slightly further from the equator were arid desert year-round
• Seed-bearing plants could survive in the driest zones because their sperm is
transported inside a pollen grain
• Tropical Everwet
– Some zones near the equator were wet and green
• Ferns (Seedless Tracheophytes), seed ferns, palm-like cycads, and
cordaites (relatives of today’s conifers)
• Cool Temperate
– Some zones were closer to the poles and had a climate that was cool
and had distinct seasons
– To conserve resources when temperatures cool, some plants lose their
leaves, growing new ones when temperatures warm up
• As plants differed based on their climate, animals that inhabited
each of these environments differed, too
Glossopteris (Leaves that have fallen)
Walchi piniformis (Conifer with Seeds)
PERMIAN REPTILES
• Diapsid reptile skull
– Youngina romeri
• Cyonosaurus longiceps
– Synaspid
What was Tetraceratops
insignis?
• First Therapsid
– Synapsid Reptile
– Group that gave rise
Mammals
Permian Reptiles
What Caused the 3rd Mass
Extinction?
• Global warming
– Scientists aren't exactly sure what triggered this mass
extinction
– Volcanic eruptions of this size would have released
enough gases to trap heat in the atmosphere
• Today, massive lava flows dating to the end of the Permian
Period cover vast areas in Siberia.
• Most devastating mass extinction in Earth’s
history
– It lasted from roughly 251 million to 250 million years
ago
– Over 90% of marine animals and 80% of land animals
(ALMOST ALL LIFE)