Beaming in your answers

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Jade Benson
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1 Bio 112 Handout for Evolution 8 This handout contains: Today s iclicker Questions Handouts for today s lecture iclicker Question #5A - before lecture Consider the hypothetical creatures on the last page of this handout. Which of the following is the most likely order of evolution for the creatures listed? A. (first) (last) B. (first) (last) C. (first) (last) D. (first) (last) E. none of the above iclicker Question #5B - after lecture Put the following events in order from the first (happened longest ago) to the last (happened most recently). (A) First plants on land. (B) First plants. (C) First animals on land. A. A then B then C. B. A then C then B. C. B then C then A. D. B then A then C. E. C then A then B. Beaming in your answers 1. Figure out your answer and select the appropriate letter (A-E). 2. Turn on your icliker by pressing the ON/OFF button; the blue POWER light should come on. If the red LOW BATTERY light comes on, you should replace your batteries soon. 3. Transmit your answer as follows: a. Press the button corresponding to the answer you ve selected (A thru E). b. The STATUS light will flash green to indicate that your answer has been received. If the STATUS light flashed red, your answer was not received; you should resend it until you get a green STATUS light. Evolution 8-1

2 Bio 112 Earth History I (the very big picture) 1 Mya = 1 Million years ago The Environment: Earth formed First life First O 2 produced by photosynthetic bacteria First humans (0.1Mya) 4,500 Mya 4,000 3,000 2,000 1, (now) too hot for life O 2 in air increases atmosphere atmosphere N 2 low CO 2 H 2 20% O 2 H 2 O 80% N 2 CO 2 no NH 3 NH 3 (toxic!) no O 2! Evolution 8-2

3 Permian Bio 112 Earth History II Time (Ma) Era Precambrian Paleozoic Carboniferous Devonian Silurian Ordovician Cambrian Period Bacteria protists (seaweed, algae, etc) Plants Animals (misc) (more later) Arthropods Water eukaryotes fish Vertebrates Mosses & ferns Seed plants Cambrian Explosion Insects Amphibians Land Reptiles Evolution 8-3

4 Ma Mesozoic Cenozoic Now Era Period Modern bacteria Quarternary Tertiary Cretaceous Jurassic Triassic Bacteria Protozoa, fungi, etc. Eukaryotes Seaweed, algae, etc. seaweed, etc. Water Lobsters, shrimp, etc. Fish Arthropods Turtles fish turtles Whales, dolphins, etc. Mosses & ferns whales Mosses, ferns Pines, ginkgos, etc. Seed plants Flowering plants flowers Insects Land Amphibians (frogs, etc.) Insects Amphibians Reptiles (lizards, snakes,..) Reptiles Birds Mammals Humans dinosaurs birds mammals Evolution 8-4

5 Bio 112 Phylogeny Demonstration Problem jointed 5 eyes eyes wings Other info: in a layer of rock that is 600 million years old, you only find type 2. in a layer of rock 200 million years old, you find 4, 5, and 6 but not 1. Suppose you found these fossil creatures on Mars. What might you conjecture about their evolutionary history? Evolution 8-5

6 Evolution 8-6

7 Bio 112: Tree thinking handout Comments on your responses to the Diversity of Life Survey : Important features that all trees must have: 1. Since the tree shows the passage of time from left to right, extant (currently living) organisms must be at the ends of branches. 2. Since some organisms fall into groups and these groups have groups within them, the tree should be hierarchical. 3. Since all organisms descended from a common ancestor, the tree should have only one root. 4. Since humans evolved from animal ancestors, humans should be part of the tree. Some sample Trees: 1) 2) 3) Evolution 8 Supplement - 1

8 4) 5) 6) 7) Evolution 8 Supplement - 2

9 Other notes: a) There are two equivalent ways to show a tree, but they can be confusing: Y s A forks A B B C C In both: the top-to bottom order does not matter. These are equivalent trees: A A C B There are differences between the two representations: C B Here, the evolutionary distances are measured as though you drove a car from A to B and measured the road miles of the entire trip. Here, the evolutionary distances are measured only horizontally. The vertical spacing is meaningless. Evolution 8 Supplement - 3

10 The most correct answer to the survey is: note that, while the branches are correct, the lengths of the connecting lines may not be. jellyfish Here is the complete tree for the Martian organisms : 600 Ma 200Ma more eyes sea stars spider horseshoe crab beetles butterflies millipedes snail leech shark fish human whale bat rat squirrel bird crocodile turtle lizard oval 2 become wings 2 become wings jointed eyes lose Evolution 8 Supplement - 4

Fossils & The Geologic Time Scale

Fossils & The Geologic Time Scale Fossils Preserved remains or traces of an organism that lived in the past. Fossils are formed when organisms die and are buried in sediment. Eventually the sediment builds