6. intraspecific relationships Flashcards
what is a territory?
the defended area where an animal lives (within a home range)
what is a home range?
an extended area beyond the territory where animals forage for food
what is a lek?
the area where animals come together to perform mating displays and attract mates for breeding
one benefit/disadvantage of a lek?
+ increases successful breeding and selecs for favourable alleles and - large group is vulnerable to predators
what is a niche?
the physical and biological factors a ppopulation occupies in its habitat
gauses law…
no two species with the same ecological niche can co-exist indefinitely: one species will outcompete the other to either undergo a change in ecological niche or become extinct
3 benefits of living in a group?
- safety in numbers= group defence
- proximity = choice of mates
- specialisation and distribution of tasks
- cooperative feeding and hunting
- increased locomotion efficiency (v formation)
- work together to raise young = inc survival
3 drawbacks of living in a group?
- increased sickness and disease
- increased vulnerability to predators
- increased competition for food, mates, space, and resources
what are the benefits of territories?
- safe place to court, mate or rear young
- enough food to survive and breed
- become familiar with the area - space, food, shelter
= species survival increases as increases reproductive success
how are territories defended?
- marking or signalling by scent
- threat displays
- fighting
what kind of agonisitc behaviour exists in intraspecific relationships?
ritualised fighting to show strength = this reduces chances or injury or death (which is unsettling and counterproductive)
what is a hierachy?
a ranking system within a population in which the strongest members are the most dominant
advantages to hierachies (list 3)
- high rank individuals are the first to feed and mate
- dominant males have more offspring than subordinates = pass on beneficial alleles to the next gen and produce a more “fit” population to inc survival rates
- protection from an alpha from predators
- group can locate and share food together
2 types of hierachy…
- linear: from most dominant to submissive
- complex: controlled by an alpha but groups within (subordinates, bonding pairs, families, labour groups)
how do animals maintain their rank in a hierachy?
positions are maintained by posture and displays - e.g. dominant stand tall, expose teeth and submissive avoid eye contact and stoop lower
how else do organisms distrubute resources?
dispersal = young are dispersed far away from parents to minimise competition
juvenilles and adults occupy different niches e.g. butterfly and caterpillar
what is monogamy?
one mate for a breeding season
what is polygamy?
more than one mate in each breeding season
when is monogamy used?
if full commitment from each parent is required to raise young in a harsh envrionment
when is polygamy used?
when parents can independently raise/or not raise young = increases reproductive fitness
what is the r strategy with benefit/disadvantage?
producing a large number of offspring (not reared)
+ low energy input for a large number of offspring
- many offspring die of starvation or predation and are less developed
what is the k strategy with benefit/disadvantage?
raising a few offspring (reared by parents)
+ offspring more likely to survive and learn beneficial survival skills
- takes significant energy input from parents
what is courtship?
behaviour in animals that initially attracts or is a prelude to mating. Feamles select for stronger or more dominant males which indicates their ability to provide better alleles and care/protect offspring.
list the pros of courtship (3 of each)
- ensures species recognition
- attracts mates from a distance
- enhances natural selection
- establishes pair bonds
- ensures psysiological readiness
= females selecte the strongest mates who will pass on favourable alleles = maintains a ‘fit’ pop.
list the cons of courtship (3 of each)
- males become injured or hurt
- attracts predators
- requires significant energy and time (not enough energy left for breeding)
give some examples of courtship rituals…
+ singing or flight displays in birds
+ male peacock displays colourful feathers
+ moths release a chemical (pheremone)
+ humpback whale calls
+ spiders vibrate their webs
