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Mesozoic Era: Biological Evolution

Mesozoic Era
1. What were some of the landmarks which occurred during the Mesozoic Era?

Time of the Dinosaurs
1. What evolutionary line did mammals evolve from?
2. What is convergent evolution? Give an example
3. What was the first bird? It has characteristics of birds and dinosaurs; what are they?
4. What evidence is there for dinosaurs being warm-blooded?
5. Describe one non-flowering plant seen before 130mya.
6. What advantages do flowering plants have over non-flowering plants?
7. What caused the K-T extinction of the dinosaurs?

Cenozoic Era
What are the highlights from this era?

Tropical Rockies
1. How are fossils identified as mammals?
2. What groups of organisms survived the KT extinction?
3. What affect did the demise of the dinosaurs have for current plants and animals?
4. What characteristics did primitive primates show which are similar to humans?

Expanding Grasslands
1. What are some new animal behaviors and what are their advantages?
2. Name three animals which were present 50mya and can still be found today?
3. What are two ways of life were established as climate warmed and dried?
4. Ancestors of whales lived on land. Why did they take to the water?
5. What scientific evidence is human evolution based on?
6. Are humans more closely related to orangutans or monkeys?
8. What types of changes occurred in humans evolution from the time of Lucy until current man?

Solution Preview

Mesozoic Era
1. What were some of the landmarks which occurred during the Mesozoic Era?
- 245 MYA (Mesozoic Era: Triassic Period)-Reptiles diversify, first dinosaurs, gymnosperms dominate plants, cycads, first mammals
- 200 MYA (Mesozoic Era: Jurassic Period)- Age of dinosaurs, first birds, first angiosperms
- 145 MYA (Mesozoic Era: Cretaceous Period)- Angiosperms diversify, dinosaurs diversify through Period, followed by mass extinction event at end of Period (.65 MYA)
See http://www.fiu.edu/~trexlerj/ages_handout.htm for all the landmarks in each era.

Time of the Dinosaurs
1. What evolutionary line did mammals evolve from?
The synapsids (see http://animals.about.com/od/mammals/a/mam101ad.htm)

2. What is convergent evolution? Give an example
This is when two evolutionary unrelated species develop common characteristics such as in the case of whales (mammals) developing fins that resemble fish (Osteichthyes). See http://en.wikipedia.org/wiki/Convergent_evolution for other examples.

3. What was the first bird? It has characteristics of birds and dinosaurs; what are they?
Archaeopteryx lithographica has been identified as the first bird. "Archaeopteryx had a full set of teeth, a rather flat sternum ("breastbone"), a long, bony tail, gastralia ("belly ribs"), and three claws on the wing which could have still been used to grasp prey (or maybe trees). However, its feathers, wings, furcula ("wishbone") and reduced fingers are all characteristics of modern birds."
See http://www.ucmp.berkeley.edu/diapsids/birds/archaeopteryx.html for more information

4. What evidence is there for dinosaurs being warm-blooded?
The evidence for dinosaurs being warm-blooded includes tomography scans that conclude that dinosaurs had hearts and a faster metabolism that more closely resemble mammals and birds ...

Solution Summary

Many questions regarding the mesozoic era are answered and explained with references.

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