Author Question: What characterized the Ordovician in terms of invertebrate life, and how does that relate to what ... (Read 9 times)

asan beg

  • Hero Member
  • *****
  • Posts: 570

What characterized the Ordovician in terms of invertebrate life, and how does that relate to what was
  happening geologically? What will be an ideal response?



Question 2

What is the Cambrian explosion? Is their appearance sudden? Why is it sudden, or why does it seem
  so? What will be an ideal response?




Anton

  • Sr. Member
  • ****
  • Posts: 302
Answer to Question 1

A major transgression in the Middle Ordovician brought to the continent a vast, shallow sea with a
warm climate, so shelly fauna increased in diversity and number. Extensive glaciation in Gondwana at
the end of the period caused a regression and a mass extinction of more than 100 families of marine
invertebrates.



Answer to Question 2

The Cambrian explosion refers to the sudden appearance of new animals in the fossil record, animals
with skeletons. So many fossils appear rapidly because of the development of skeletons, which
fossilize much better. Also, these advances helped life to proliferate.




Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

Studies show that systolic blood pressure can be significantly lowered by taking statins. In fact, the higher the patient's baseline blood pressure, the greater the effect of statins on his or her blood pressure.

Did you know?

In the ancient and medieval periods, dysentery killed about ? of all babies before they reach 12 months of age. The disease was transferred through contaminated drinking water, because there was no way to adequately dispose of sewage, which contaminated the water.

Did you know?

Malaria mortality rates are falling. Increased malaria prevention and control measures have greatly improved these rates. Since 2000, malaria mortality rates have fallen globally by 60% among all age groups, and by 65% among children under age 5.

Did you know?

Many people have small pouches in their colons that bulge outward through weak spots. Each pouch is called a diverticulum. About 10% of Americans older than age 40 years have diverticulosis, which, when the pouches become infected or inflamed, is called diverticulitis. The main cause of diverticular disease is a low-fiber diet.

Did you know?

GI conditions that will keep you out of the U.S. armed services include ulcers, varices, fistulas, esophagitis, gastritis, congenital abnormalities, inflammatory bowel disease, enteritis, colitis, proctitis, duodenal diverticula, malabsorption syndromes, hepatitis, cirrhosis, cysts, abscesses, pancreatitis, polyps, certain hemorrhoids, splenomegaly, hernias, recent abdominal surgery, GI bypass or stomach stapling, and artificial GI openings.

For a complete list of videos, visit our video library