3.2 Flashcards
state the definition of symbiosis
symbiosis is the intimate co evolved relationship between two members of two different species.
Explain parasitism
the parasite benefits in terms of energy and nutrients and host is harmed by loss of these resources. (ticks, fleas, tapeworms)
Explain mutualism
Both mutualistic partner species benefit in an inter dependent relationship ( nile crocodile, Egyptian plover)
parasites..
parasites have limited metabolism and cannot survive without contact with a host
parasite transmissions ; direct contact
direct skin to skin contact. e.g ringworm lice
parasite transmission ; resistant stages
allows the parasite to survive in extreme conditions by lying dormant until conditions are optimal e.g spores in fungi/ bacteria.
parasite transmission ; vectors
an vector is an organism that carries the parasite from an infected individual and directly infects new hosts. e.g malaria uses the insect vector of a mosquito.
secondary hosts
a secondary host is an organism that hosts part of the parasite’s lifecycle and then transfers it indirectly through hosts.
secondary host example
parasite - pork tapeworm. primary host - human . secondary host - pig
social hierarchy
this is a rank order within groups of animals consisting of dominant and subordinate members. Dominant members carry out ritualistic (threat) displays while subordinate members carry out appeasement behaviour.
E.g pack animals, wolves/hyenas. Gorillas/chickens.
benefits of this behaviour ; social behaviour
- reduces conflict
- increases the chance of the dominant’s favourable
genes being passed onto offspring. - form alliances to increase social status in groups.
cooperative hunting
animals that hunt together in groups. E.g lions/wolves
benefits of this behaviour ; cooperative hunting
- subordinate animals benefit as well as dominant
animals. - may gain more food then foraging alone.
- larger prey can be hunted.
- increases chance of hunting success.
- less energy is used per individual.
social Defence
groups that act together to defend or raise alarm.
E.g flocks of birds, herd animals (bisons).
benefits of this behaviour ; social defence
- increases the chance of survival as some individuals
can watch for predators while others can footage.
E.g meerkats. - groups adopt specialised formations when under
attack to protect their young.
Define Altruism
Altruism is behaviour that harms the donor individual but benefits the recipient.
E.g donating food to the recipient.
Define reciprocal altruism
reciprocal altruism is when when the roles of donor and recipient later reverse. often occurs in social animals.
E.g vampire bats exchanging blood meals.
Kin selection and altruism
Behaviour that appears altruistic (often isnt) can be common between a donor and recipient if they are related (kin).
The Donor does benefit in kin selection, in terms of genetics, as this behaviour between related animals increases the chances of survival of shared genes in the recipient’s future offspring.
social insects examples and roles within colonies
examples; bees, wasps, ants, termites.
Roles Within Colonies;
- raise related offspring
- defending the hive
- collecting pollen and nectar
- waggle dances to show direction of food
- the role of male bee drones it to fertilise the queen’s e
egg
how sterile workers increase the survival of shared genes in social insects
most members of the colony are related sterile workers who cooperate with other close relatives to raise closely related offspring and in doing so increase the survival of shared genes.
primate behaviour
primates often live in social groups and have complex behaviours to prevent conflict
complex social behaviours ; grooming, facial expressions , body posture and sexual presentation
- These behaviours support the social hierarchy and
reduce conflict. - This reduces conflict through ritualistic displays and
appeasement behaviour. - Alliances form between individuals which are used to
increase social status within the group.
