exam 4 ch 18.4

Question 1

Ocean species diversify rapidly, fish evolve, & plants colonize the land.

Answer 1

Ordovician Era:

Question 2

A three-fold increase in species diversity
occurs when oxygen levels rise in oceans

Answer 2

Great Ordovician Biodiversification Event (GOBE):

Question 3

Trilobites and large arthropods diversify.

Answer 3

Arthropods dominate:

Question 4

Giant 20-30ft long Nautiloids (cephalopods).

Answer 4

cephalopods dominate:

Question 5

(aka Sea scorpions) extinct marine arthropods up to 8.5 feet long

Answer 5

Eurypterids evolve:

Question 6

Type of Sponges (stromatoporoids) & tabulate corals were the main reef builders

Answer 6

Tabulate corals evolve:

Question 7

Spores from land plants in the Early Ordovician indicating the presence of
non-vascular bryophytes (liverworts, hornworts, mosses).

Answer 7

First land plants:

Question 8

Macro-fossil evidence of liverworts, hornworts, mosses (Bryophytes)
and plants with stomata by the Middle Ordovician

Answer 8

First fossils of land plants:

Question 9

Waxy cuticles allow Bryophytes to diversify on landscape by preventing water loss.

Answer 9

land plants:

Question 10

Macro-fossil evidence of plants with stomata by the Middle
Ordovician

Answer 10

First fossils of land plants:

Question 11

Early jawless fish that had
scales, brains, and facial armor made from fused-toothlike pieces.
Franz

Answer 11

Some vertebrates evolve into Ostracoderms “shell-skinned”:

Question 12

The expansion of early land plants (bryophytes) decreased
global CO2 levels triggering a glaciation event.

Answer 12

Ordovician-Silurian Extinction:

Question 13

The expansion of early land plants (bryophytes) decreased global
CO2 levels triggering a glaciation event causing a pulse of extinctions followed by another pulse of extinctions when the climate warmed back up.

Answer 13

Ordovician-Silurian Extinction Event: