February 21, 2002

1
Lecture 13

• February 21, 2002
• Chapter 18 The Evolution of Animal Diversity
• Chapter 31 Plants

2
Learning Objectives (1 of 2)

• Define
• Class Aves
• Class Mammalia
• List
• The reptile-like characters of Archaeopteryx
• Recite
• 2 pieces of evidence that birds evolved from
  reptiles
• 3 basic types of mammals

3
Learning Objectives (2 of 2)

• Recall
• The species of General Sherman
• Contrast
• Monocots and Dicots
• Xylem and phloem

4
Reptiles

• Evolved from amphibians
• Can live on land for entire life
• 2 Major features
• Developed amniotic land egg to do this
• No longer require water for reproduction
• Water-proof skin
• To conserve water

5
Ex Dinos are Reptiles
6
Ex Lizards are Reptiles
7
Ex Crocodilians are Reptiles
8
Bird Evolution

• Believed to have evolved from small, carnivorous
  dinosaurs
• Dino hand bones similar to bird wing bones
• When given certain hormones, chicken embryos will
  develop teeth!

9
Archaeopteryx

• A very early bird!
• Reptilian characteristics
• Long tail
• Wing claws
• Teeth
• Scales on feet

10
Class Aves

• All birds
• Have feathers!
• Are endothermic (warm-blooded)
• Lay eggs

11
Class Mammalia

• All mammals
• Have fur (yes, even whales dolphins)
• Feed their offspring milk
• Are endothermic

12
Three Basic Kinds of Mammals

• Monotremes
• They lay eggs!
• Include platypus
• Marsupials
• Carry young in pouch
• Ex kangaroos, opposums
• Eutherians (placentals)
• Longer pregnancy
• More developed young

13
To Sum Up
14
Question

• Which group evolved earliest in the history of
  life?
• Fish
• Dinosaurs
• Mammals
• Birds

15
Another Question

• Are birds animals?
• Are fish animals?

16
7th Inning Stretch
17
Worlds Biggest Plant

• The General Sherman Tree
• Species is Sequoiadendron gigantea
• Central California
• 2500 years old!!!
• National Park Service site
• US Geological Survey site

18
Angiosperms

• These are flowering plants
• Two basic types
• Monocots
• Dicots

19
Monocots

• Have one seed leaf
• Root network very fibrous
• Leaves have parallel veins
• Examples orchids, bamboos, palms, grasses
  (including rice, other grains)

20
Dicots

• Have two seed leaves
• One main taproot plus root hairs
• Leaves have multiply branched veins
• Ex trees, shrubs, carrots

21
Question

• Where would we classify pine trees?

22
Answer

• Trick question they arent angiosperms
• Theyre gymnosperms (no flowers!)

23
Conductive Tissues

• Xylem
• Phloem

24
Xylem

• Contains water-conducting cells
• Carries water and nutrients toward the leaves

25
Phloem

• Contains food conducting cells
• Transports sugars to tissues, roots