10.31 Hawaiian biota

Question 1

Zygote mortality

Answer 1

• Post-zygotic isolation.
• Occurs when a successfully fertilized egg begins development, but zygote is not viable and fails to complete development.
• Prevents population interbreeding.

Question 2

Hybrid inviability

Answer 2

• Post-zygotic isolation.
• When gametes fuse, development progresses, but offspring cannot survive to adulthood.

Question 3

Hybrid sterility

Answer 3

• Post-zygotic isolation.
• Offspring survive to adulthood, but cannot reproduce.

Question 4

Low fitness

Answer 4

• Post-zygotic isolation.
• Offspring survive and can reproduce, but have very low fitness in the wild.
• E.g. dog wolf hybrids almost always killed by wolf packs.

Question 5

Characteristics of Hawaiian biota

Answer 5

• Fewer types of organism, but extremely diverse.
• No reptiles, amphibians.

Question 6

Why Hawaii has so few orders/families?

Answer 6

• Most isolated landmass in the world.
• Very recent island formed by volcanoes.

Question 7

Why Hawaii has so many species?

Answer 7

• Adaptive radiation:
  Being first to an island = intra-specific competition + exponential increase = competition is a dominant force.