3.3b Species on the Red List

Question 1

What is an example of an extinct species?

Answer 1

Dodo

Question 2

What are some pressures on the dodo?

Answer 2

• Human settlement on islands bringing non-native (predator) species
• Dodos only produced one offspring (lay one egg)
• Flash flood occurred as the species was almost extinct - reduce any remaining chance of survival
• They were not adapted to predators (eg. were not afraid of humans as they had never encountered predators before..)

Question 3

What is the importance/ ecological role of the dodo?

Answer 3

• Primary consumer
• Diet consisting of nuts, fruits, seeds and insects

Question 4

What are some consequences of the extinction of dodos?

Answer 4

• Became extinct 80y after its discovery
• Some trees stopped germinating because the dodo usually ate the fruit that was grown on these trees. And only through the dodo’s digestive system could these seeds grow.
• Animals preying on dodo bird –> population fell as less food

Question 5

What is an example of a critically endangered species?

Answer 5

African Forest Elephant

Question 6

What are some pressures on the African Forest Elephant?

Answer 6

• Sharp declines in population since 2008
• Poaching
• Habitat loss: conversion of forests to agricultural land

Question 7

What is the importance/ ecological role of the African Forest Elephant?

Answer 7

“Ecosystem Engineers”
- Physically transform the forest as they move through it and feed
- Create light gaps by knocking down trees
- Trample vegetation to keep undergrowth clear
- Shatter rotting logs to speed up decomposition

Question 8

What are some consequences of the extinction of the African Forest Elephant?

Answer 8

• The bush would replace grassland by thorny scrub
  –> There wouldn’t be any herbivores because there wouldn’t be places for them to graze!

Question 9

What is an example of a species that has recovered?

Answer 9

Mountain gorillas

Question 10

What are some pressures on the Mountain gorillas?

Answer 10

• Extremely poor region
• High political instability
  –> More people moving into the forests for housing, foods and materials
  –> Over 500,000 people live near mountain gorilla habitat currently
  ! Degradation of habitat !
• Gorilla tourism that isn’t well managed
• Armed conflict in the DRC
• Mining industries

Question 11

What is the importance/ ecological role of the Mountain Gorillas?

Answer 11

• Lives in the forests in mountainous regions of the DRC
  –> plays a key role in maintaining the biodiversity of their forest homes by spreading the seeds of the trees they eat and by opening up gaps in the trees as they move around, letting in light and helping sun-loving plants grow

Question 12

What are some consequences of the extinction of the Mountain Gorillas?

Answer 12

• Still endangered currently, but recovered with now over 1,000 individuals in the wild
  –> Many wildlife groups are protecting them in their habitats