Lecture 6: Animal Feeding Strategies

Question 1

Name four major feeding strategies

Answer 1

1. Suspension/filter feeding
2. Fluid feeders
3. Substrate feeders
4. Bulk feeders

Question 2

Define suspension feeders

Answer 2

Use some kind of apparatus to filter food out of water/air
Common in aquatic systems
Ex- Krill use ‘feeding basket’ made from front appendages - movement of appendages create vortices drawing more water and food towards mouth

Question 3

Define fluid feeders

Answer 3

Suck nutrients from living host

Ex - phloem, blood

Question 4

Define substrate feeders

Answer 4

Live in or on their food

Ex- Maggots and caterpillars

Question 5

Define bulk feeders

Answer 5

Most animals are bulk feeders
Eat relatively large pieces of food
Ex- pythons, humans

Question 6

Adaptations of herbivores

Answer 6

Frugivores (fruit)
Folivores (leaves)
Granivores (seeds)
Nectarivores (nectar)
Polynivores (pollen)
Xylophages (wood)
Grazers (grass, low vegetation)
Browsers (woody vegetation)

Question 7

Name 3 challenges of herbivory

Answer 7

1. Overcome plant defenses - physical, chemical, other
2. Acquire plant material
3. Digest it

Question 8

What adaptations do herbivores have to deal with plant physical defenses?

Answer 8

Hardened lips and tongue, i.e. giraffe
Agility to avoid thorns
Specialised teeth

Question 9

How to herbivores tolerate plant chemical compounds?

Answer 9

Chemical breakdown by novel biochemical pathways
Some species alter feeding patterns
Toxins are used by some caterpillars to make themselves toxic

Question 10

Herbivore adaptations to help them acquire food:

Answer 10

Molluscs have radula - contains teeth made of chitin
Constantly growing to replace worn teeth
Grinds it against plant material

Question 11

Define coprophagy

Answer 11

A way to recover lost nutrients by eating faeces

Ex- rabbits and rodents have bacteria in large intestine to help with this

Question 12

Describe ways predators have adapted to catching & eating prey

Answer 12

1. Sit & wait - camouflage
   
   • > praying mantis
2. Lures - prey are lured to their deaths with moving light
   
   • > Arachnocampa ‘glow worms’
3. Venom - paralyze prey by injecting venom
   
   • > blue ring octopus
4. Speed - predators very fast over short distances
   
   • > cheetahs
5. Strength and stamina
   
   • > African wild dogs

Question 13

Describe ways prey have adapted to avoid being eaten

Answer 13

1. Camouflage
   
   • > leaf insect
2. Poisons & warning colours
   
   • > poison dart frog
3. Mimicry - poisonous model and non poisonous model
   
   • > butterflies
4. Living in groups

Question 14

Define aposematism

Answer 14

Poisonous species are brightly coloured