Reproduction on land & freshwater

Question 1

Consequences of internal fertilization

Answer 1

1. Complex copulatory behaviour = sexual selection
   - adults rarely hermaphroditic
2. Embryos all lecithotrophic
   - eggs must have enough nutrients

Question 2

Lecithotrophic def

Answer 2

Larvae that rely on maternal reserves to fuel larval development and do not require (or are unable) to feed on exogenous food items

Question 3

Why are Arachnida, Myriapoda & Insecta so successful? (2)

Answer 3

• Have waterproof external covering
• Development may be internal

Question 4

Incomplete metamorphosis def

Answer 4

Develop into adults with minor changes in form

Question 5

Complete metamorphosis def

Answer 5

Undergo a total reorganization of internal & external anatomy when they pass thru pupal stage of life cycle

Question 6

Parent care modes (3)

Answer 6

• Non carers
• Guarders
• Provisioners

Question 7

Mean egg size always … with body size regardless of care

Answer 7

INCREASES

Question 8

Egg size does/ does not increase with higher levels of care?

Answer 8

Does not

Question 9

Why insects showing parental care may lay large eggs (guarders AND provisioners)?

Answer 9

– Increased developmental time increases period of protection
– Decreased mortality of eggs
– Fewer larger eggs decreases sibling conflict after hatching