Eggs

Question 1

Q1: How did vertebrates like Camarasaurus start life?

Answer 1

A1: Vertebrates like Camarasaurus started life as a single cell, a fertilized egg.

Question 2

Q2: Which came first, the chicken or the egg? What would paleontologists say?

Answer 2

A2: Paleontologists would say the egg came first. Long before chickens evolved, land-dwelling animals developed the ability to lay hard-shelled eggs.

Question 3

Q3: What are the advantages and disadvantages of hard-shelled eggs?

Answer 3

A3:

Advantages:

Water retention.
Protection from predators.

Disadvantage:

Difficulty in oxygen exchange due to the hard shell.

Question 4

Q4: Why did land animals develop hard-shelled eggs?

Answer 4

A4: Land animals developed hard-shelled eggs to prevent them from drying out in dry environments, as eggs laid in water didn’t face this problem.

Question 5

Q5: How did the development of hard-shelled eggs benefit terrestrial animals?

Answer 5

A5: Hard-shelled eggs allowed terrestrial animals to live farther from water and avoid returning to water to lay their eggs, giving them a reproductive advantage.

Question 6

Q6: Why did hard-shelled eggs need to remain relatively thin?

Answer 6

A6: Hard-shelled eggs needed to remain thin to allow oxygen exchange with the air, as embryos inside the eggs need oxygen to survive.

Question 7

Q7: Which dinosaur family laid the largest eggs, and how big were they?

Answer 7

A7: The largest known dinosaur eggs belonged to theropods, specifically an oviraptorosaurid from China, and were about half a meter long.

Question 8

Q8: How does an eggshell facilitate gas exchange for a developing embryo?

Answer 8

A8: The eggshell has small pores that allow oxygen to come in and carbon dioxide to go out, functioning like a lung for the developing embryo.

Question 9

Q9: What does the cube-square law explain about egg size?

Answer 9

A9: The cube-square law explains that as an egg gets larger, its surface area grows slower than its internal volume, limiting the ability to exchange gases and imposing a maximum size for eggs.

Question 10

Q10: Why can’t dinosaur eggs grow indefinitely large, no matter the size of the dinosaur?

Answer 10

A10: Dinosaur eggs can’t grow indefinitely large because the surface area for gas exchange becomes too small in proportion to the egg’s volume, leading to suffocation of the embryo if the egg is too big.