c ommunities. all populations interacting at any particular time in a defined habitat. - give me an...
TRANSCRIPT
COMMUNITIES
COMMUNITIES
All populations interacting at any particular time in a defined habitat.
- Give me an example?
COMMUNITIES
All populations interacting at any particular time in a defined habitat.
Some are temporary (eg. a rotting log) and some last a long time (eg. Forests)
Other examples?
COMMUNITIES
All populations interacting at any particular time in a defined habitat.
Some are temporary (eg. a rotting log) and some last a long time (eg. Forests)
Three characteristics common to most communities:
- The more different species in a community, the more stable it is = species diversity. And vice versa. Eg. Tundra – unstable b/c low species diversity, rainforest – stable.
Three characteristics common to most communities:
- A few organisms are present in a large number or great biomass (weight of living matter). These dominate the community.
Three characteristics common to most communities:
- A few organisms are present in a large number or great biomass (weight of living matter). These dominate the community. A great number of other organisms are relatively rare, but they can play an important role.
Three characteristics common to most communities:
- A few organisms are present in a large number or great biomass (weight of living matter). These dominate the community. A great number of other organisms are relatively rare, but they can play an important role.
- EG. A beetle that only eats one plant may keep it in check.
Three characteristics common to most communities:
- Always more producers (usually plants) than consumers. (One exception – the sea). Phytoplankton don’t have higher numbers than animals that eat it, yet they reproduce so quickly they can keep up.
Three characteristics common to most communities:
- Always more producers (usually plants) than consumers. (One exception – the sea). Phytoplankton don’t have higher numbers than animals that eat it, yet they reproduce so quickly they can keep up.
- ** Communities are named from the highest biomass – eg a kauri forest.
COMPOSITION OF A COMMUNITY
All organisms can be grouped according to their feeding or trophic levels.
1. Producers –
COMPOSITION OF A COMMUNITY
All organisms can be grouped according to their feeding or trophic levels.
1. Producers – make their own foodPhotosynthesisers = take energy from
sunlight. Together with water and C02 they make glucose.
COMPOSITION OF A COMMUNITY
All organisms can be grouped according to their feeding or trophic levels.
1. Producers – make their own foodPhotosynthesisers = take energy from
sunlight. Together with water and C02 they make glucose.
Chemosynthesisers = usually bacteria. Same thing but energy from chemical reactions.
CHEMOSYNTHESIS
2. Consumers – can’t make own food.
2. Consumers – can’t make own food.- Herbivores = animals that eat all parts of
plants. Sap, leaves, roots, pollen etc.
2. Consumers – can’t make own food.- Herbivores = animals that eat all parts of
plants. Sap, leaves, roots, pollen etc.- Carnivores = animals that eat other animals.
Predators – hunt, kill, and eat.
2. Consumers – can’t make own food.- Herbivores = animals that eat all parts of
plants. Sap, leaves, roots, pollen etc.- Carnivores = animals that eat other animals.
Predators – hunt, kill, and eat.- Scavengers – live off dead animals killed by
something else.
2. Consumers – can’t make own food.- Herbivores = animals that eat all parts of
plants. Sap, leaves, roots, pollen etc.- Carnivores = animals that eat other animals.
Predators – hunt, kill, and eat.- Scavengers – live off dead animals- Parasites – live in or on living host. Endo-
inside, and Ecto-outside.
ENDO/ECTO
2. Consumers – can’t make own food.- Herbivores = animals that eat all parts of
plants. Sap, leaves, roots, pollen etc.- Carnivores = animals that eat other animals.
Predators – hunt, kill, and eat.- Scavengers – live off dead animals- Parasites – live in or on living host. Endo-
inside, and Ecto-outside. - Decomposers = bacteria and fungi that break
down dead bodies to release the nutrients.
INTRA-SPECIFIC RELATIONSHIPS
Either cooperative or aggressive.
INTRA-SPECIFIC RELATIONSHIPS
Either cooperative or aggressive. Cooperative – includes courtship, looking
after young, hunting in packs, defending the group.
INTRA-SPECIFIC RELATIONSHIPS
Either cooperative or aggressive. Cooperative – includes courtship, looking
after young, hunting in packs, defending the group.
Aggressive – fighting for mates, territory, keeping up pecking order etc.
INTER-SPECIFIC RELATIONSHIPS
Mutualism – both partners benefit.
(lots of examples which we have already discussed/watched jot down some)
INTER-SPECIFIC RELATIONSHIPS
Mutualism – both partners benefit. Commensalism – one species benefits while
the other is unaffected. EG. A fish called a remora. Hitches a ride on a
shark, and when the shark attacks the remora feeds on scraps then hitches another ride. The sharks are indifferent, yet the remora gets lots of food and doesn’t use energy.
INTER-SPECIFIC RELATIONSHIPS
Mutualism – both partners benefit. Commensalism – one species benefits while
the other is unaffected. Antibiosis – one species is harmed and the
other is indifferent.
EG. Blue green mould on rotting oranges/lemons is penicillum – which produces a chemical called penicillin which inhibits bacteria. Hence, antibiotics.
INTER-SPECIFIC RELATIONSHIPS
Mutualism – both partners benefit. Commensalism – one species benefits while
the other is unaffected. Antibiosis – one species is harmed and the
other is indifferent. Exploitation – One species benefits, while the
other is harmed.
EG. Most examples of herbivores, carnivores, and parasites etc.