Animal associations: Introduction

what do intraspecific interactions include? (homogenetic assocations)

herd/flock associations, parental care, pairing, colonial life

what doe interspecific interactions include? (heterogenetic associations)

commensalism, mutualism, predation, parasitism

what are the challenges that every animal faces

How to obtain nourishment
• How to shelter from the elements
• How to find a mate and reproduce
• How to disperse to reduce competition for food, shelter
and mates

what is the 1879 definition of symbiosis

the living together of unlike organisms

what are herd and flock associations

a social grouping of animals of the same species including flock, herd, school, and swarm

what are the advantages of herd/flock associations

Safety in numbers – individual level lower predation and
parasitism (ectoparasites like biting flies/mosquitoes)
• Aerodynamics- Conserves their energy- each bird flies
slightly above the bird in front of him, resulting in a reduction of
wind resistance.
• Communication and coordination within the group
• Protection while foraging
• Efficient foraging
• Finding a mate
• Raising families

what are the disadvantages of herd/flock associations

Visibility to predators
• Usually leads to predators targeting old and young
• Competition for food and mates
• Infectious disease (parasites and pathogens)

what is parental care

parental behaviour that arose and/or is maintained for the purpose of increasing offspring fitness

what is the trade off that comes with parental care

the greater the amount of care, the fewer the number of offspring

monoecious (hermaphrodite)

an
organism having both the male and
female reproductive organs in the same
individual (common in invertebrate
animals)

dioecious

an organism having the
male and female reproductive organs in
separate individuals
• Monogamous: an individual
having only one mate at a time
• Polygamous: an individual
having more than one mate at a
time.

colonies

a group of animals of one kind living closely together or forming a physically connected structure

advantages of colonies

1. Safety in numbers
2. Communication and
coordination within the group
3. Efficient foraging
4. Mating
5. Raising families

disadvantages of colonies

1. Visibility
2. Competition
3. Hierarchy within colony members

what are the different types of predation in simple terms

true predation, grazing/micropredator, parasites and parasitoids

amensalism

one species is harmed or inhibited while the other species remains relatively unaffected (it neither benefits nor is harmed)

competition

both species get less than they would if they were alone

neutralism

where two species coexist in the same environment but have no measurable effect on each other

commensalism

a relationship between two species in which one species benefits and the other is not affected eg cleaning, protection, transport

phoresy

hitching a lift on another organism

give two examples of phoresy

sexton beetle and mites, spinner dolphin and remora fish, The remora hitch a ride of their
hosts
• Spinner dolphins in particular
breach explosively in order to get
rid of their passengers

mutualism

a relationship between two species in which both benefit from the association

example of mutualism

Cleaner and client fish:
•Cleaners gain food (+) in the form of ectoparasites, bacteria and necrotic tissue
from the body or surface of the ‘client’ fish
•Clients are protected from infection (+)
•Cleaner fish often hold territories with ‘cleaning stations’ that their clients visit – and
visit more often when they have parasites.

mutualism in coral and algae

a relationship where one resource is traded for another, • The algae (zooxanthellae) get inorganic nutrients from the corals
• The corals get sugars (by-products of photosynthesis) from the algae.
• When a coral 'bleaches' it is actually kicking out the zooxanthellae
that live in it, so all you see is the coral's skeleton, which is white

mutualism in anemones and clownfish

a relationship where one service is traded for another, Anemones provide clown fish with protection from predators
(which cannot tolerate the stings of the anemone's
tentacles) and the fish defend the anemones against
butterfish which eat anemones

mutualism, oxpecker and antelope

Antelope is groomed-ectoparasites removed
Oxpecker gets food (e.g. ticks) from the antelope

mutualism, humans and farming

Humans benefit from agriculture by having a reliable food
source
• Crop and livestock species are cultivated and protected by
humans for their benefit, at the expense of wild species

mutualism, human and their microbiome

The human
microbiome –
the community of
microbes, their
genomes and
environmental
interactions
found on a
human

numbers and functions of human microbiome

parasitism

relationship between two species in which one species benefits at the expense of the other

ectoparasites

live on the body surface of the host

endoparasites

live inside the host’s
body may be intercellular (inhabiting spaces
in the host’s body) or intracellular
(inhabiting cells in the host’s body)
e.g. Botfly larvae in a horse
’s stomach

interspecific interactions from an ecologists viewpoint

interspecific interactions from another perspective