Interspecific and Intraspecific Relationships

Territory

• An area where an animal lives and the area that it defends from other animals of the same species

• Contains their resources such as nesting sites, food and mates

Home range

• A wide area of occupation which is not defended

• Used as a food source or to find a mate

Lek

Where (usually) males come together and perform mating displays, often competetitively, to attract female mates for the purpose of breeding

Ecological niche

Physical and biological conditions or factors a population/species faces in its habitat

Gauses Law

Two species with the exact same ecological niche will not co-exist indefinitely

Intraspecific Competetion

Competetion between members of the same species for food, space, territory, dominance, breeding partners etc

Intraspecific competetion impacts

• Always results in a decrease of the reproductive rate of the population

• Density-dependent manner - as population densities increase, the resources available to each individual become fewer, and intra-specific competition increases

Adaptive advantages of territories

• Ensures enough space, food for each animal

• Spreading out reduces the spread of disease and parasites

• Most successful males hold best territories, ensures best genes are passed onto offspring

• Once territories established, resources divided and fully committed

• Territories ensure a safe protected home for young, or place to breed for communual breeding grounds

• Animal has an area which it is familar and can learn where resources are

• Reduce intraspecific competetion

Disadvantages of territories

• Territorial animals must do everything themsleves and protect their territories from other threats

• Lack of group protection increases risk of predation

• Territory may be encroached on by member of the same specieis who is stronger

• Maintaining a territory has an energy demand on each individual

• More resources for the animal but they would have to keep fighting to defend their territory

• Males have to challange and duel to get females attention

Establishing and maintaining a territory

• Agonistic behaviour

• Vocalisation

• Marking with scent or scratching

• Fights

Agnostic Behaviour

Range of ritual threat displays and ritual submission

• Confrontation takes form of ritualised display

• Recognisable to both parties

• Signifies strength, power, ability to win the fight

• Lessens the necessity for an actual fight as weaker animal will usually submit

Marking with scent

• Odour may show an individuals identity, status, health and age

• Some animals may leave scent along the border of their territory

• Scent lets other animals know this territory has an owner

Advantages of living in groups

• Safety in numbers

• Being able to warn or fight off predators

• Help each other find food, defend territories and raise young

• Co-operative social behaviours assists survival of all individuals

• Mates in closer proximety

Disadvantages of living in groups

• Disease is more common in close groups

• Competetion for food and space

• May be increased vulnerability to predators as large groups are more noticable

Hierachy

Ranking system with the strongest and most dominant members on top and the weakest, most submissive members at the bottom

Linear hierachy

Simple progression from most dominant to most submissive

Complex hierachies

Structures involving different groups such as subordinate groups, family groups, bonding pairs and labour groups, often all controlled by a dominant, alpha member

Benefits of hierachies

• Reduces intraspecific competition

• Efficent method of resource distribution

• Members of the group ‘know their place’ so aggression is reduced

• Higher ranked individuals eat first, mate more often and have more resources to invest in survival of offspring

• Positions in the hierachy can change depending on age, gender, body size, intelligence and aggressiveness

Maintaining hierachies

• Rank order is reinforced with aggressive and submissive vocalisations or displays

• Auditory or visual signals are usually important for recognition of individuals

• Appeasement behaviour, such as exposing vulnerable parts of the body, is often important for subordinates maintaining the hierachy

Monogamy

Pair bond endures for a nesting season, entire breeding season, several successive breeding seasons or life

Polygyny

• Each breeding male has a hareem of females

• Increases reproductive success of male

• Females offspring inherit the strongest genes

Polyandry

• One female has many males

• Increases chance of reproductive success

• Females may recive food offerings from prospective males

• Males can’t ensure offspring are theres so they don’t attack, increases survival rate of females offspring

R-Strategy

High numbers of offpsring, little to no parental care, low survival rates

K-Strategy

Low numbers of offspring, high amount of parental care, high survival rates

Oviparous

Animals which produce eggs which hatch later

Viviparous

Animals which give birth to live young

Altricial

Born or hatched naked, blind and helpless

Precocial

Born or hatched well covered, active and rapdily independent

Courtship behaviour

Behaviour patterns and rituals that lead up to mating

• Helps ensures male and female recognize each other as the same species as rituals are species specific

• Helps synchronise male and female repoductive behaviour

• Occur even in pairs which mate for life

Courtship displays and signals

• Olfactory - pheromones

• Auditory

• Visual

• Tactile

Disadvantage of coutship

• Disadvantage of bright colours - increase risk of predation

• Given the advantage of attracting a mate outweights this, bright colours will be selected for

Altruism

Individuals making an effort to benefit others of their species, even when they are not closely related

Kin Selection

Altruistic behaviour towards close relatives

Altruistic behaviour

• By helping care for young relatives, increases survival chance

• Carer increases success of own genes, as closely related

• Carers gain useful experience

• Behaviour has been shaped by natural selection

Exploitation

• predation

• herbivory

• Parasitism

One species benefits and one species is harmed

Commensalism

Relationship between two different species where one benefits while the other is unaffected.

Mutalism

Relationship between two different species where both specieis benefit

Interspecific competetion

Competetion for resources between members of different species

• Negative impacts for both species

Niche specialisation

Species in similar niches have minor diffierences so they can both survive in the same habitat

Ecological niche

Its way of life - where it lives, what it eats, adaptions it has to survive, how it breeds, when it is active, interrelationships it has, its role in the ecosystem

Allelopathy

Plants reduce competetion from other specieis by producing chemicals that inhibit rival growth

Predation

Where one animal hunts and feeds on another

Herbivory

Type of predation, invovles one animal species feeding on a plant species

Parasitism

One organism (parasite) living on or inside another species (host)

Batesian mimicry

Harmless species mimics a dangerous one

Mullerian mimicry

Where two unpalatable species mimic each others warning signals

Symbiosis

Close relationships between different species

Camoflage (crypsis)

Blending into surroundings

Aposematic

• Warning colouration

• Animal which defends itself with harmful chemicals uses specific colouration to warn predators

Autotomy

Shedding of parts when attacked

Synchronised breeding

• Strategy to avoid predation

• With high numbers of eggs laid/released at the same time, predators eat a smaller proportion than if eggs were laid over a long period of time

Prey strategies to avoid predation

• Safety in numbers

• Camoflage

• Aposematic colouration

• Mimicry

• Autonomy

• Syncronised breeding

• Visual deception

• Chemicals

Safety in numbers

• Animals can detect predators easier

• Dilution effect - less likely to be captured

• Confusion effect - hard for predators to concentrate on single prey

Antibiosis/Ammensalism

One species is harmed and the other is unaffected