L29 Interactions between Organisms - Mutualisms Flashcards
what are INTRA specific interactions?
happen within species - group living, competition, reproduction, sexual conflict
what are INTER specific interactions?
happen among species - predation, herbivory, competition (food and space), mutualism, commensalism, amensalism, parasitism
what happens if a seedling was to develop between 2 plants?
insufficient moisture available for establishment - outcompeted
what happens when precipitation levels change in relation to plants?
plant density will change - they are interrelated
what tree will win the competition for space?
the tallest one - it will shade out the others
what is commensalism?
an ecological relationship in which one benefits and the other is not harmed or helped in any significant way
what is amensalism?
competition with no effect on winning competitor and loser suffers
give an example of commensalism
examples Barnacles growing on whale
and spider web inbetween deer antlers
give an example of amensalism
trees competing for space
mature tree drops a seed and doesn’t suffer or benefit from it growing
what is parasitism?
organism lives on prey and eats cell contents tissues or bodily fluid, they harm but do not kill
what is symbiosis?
2 organisms in close association with one another which are benefiting from one another
give an example of mutualistic symbiosis?
lichen
fungi produces habitat for algae, algae photosynthesises and produces nutrients for fungi
give an example of a parasitic symbiosis
caterpillar parasites - 2 organisms living together, one benefits and one suffers up until host is killed
what is pollination?
a mutualistic/commensalism interaction between species
give an example of pollination mutualism
bee gets nectar food from flower and transports pollen
why can pollination be an example of commensalism?
neutral benefit for the flower because it can benefit from wind pollination
give an example of pollination commensalism
orchids produce chemical bee pheromones causing them to pick up pollen (bee doesn’t suffer, plant benefits)
when does fungal mycelium form?
in the presence of plant roots
what type of relationship does mycellium and plants have?
mycorrhiza mutualism
-mycorrhiza enhances competitive ability
what is a type of plant parasitism?
grazing - plant loses photosynthetic material while deer is getting nutrition
what is a niche?
specific set of biotic and abiotic resources in an environment that an organism uses to thrive
what influences where an organism lives?
optimal conditions will determine where an organism situates itself to best meet its required niche
what is a fundamental niche?
the basics needed for an organism to survive
what happens when individual specie’s niches overlap?
this overlapping leads to interactions
what is a realised niche?
a more specified niche inside of a fundamental niche of another organism
what is an example of fundamental and realised niche?
Barnacle growth on tidal zone
what did Connell 1961 realised niche experiments find out?
upper part of tidal zone - chthamalus
lower part - balanus
1) the realised niche of balanus is within chthamalus fundamental niche
2) when both are present they have two separate realised niche
what happens when other species get involved in a species fundamental niche?
the fundamental niche contracts into realised niche
what is resource partitioning?
niche differentiation - a process of natural selection that will force competitors to use resources differently
what are the two types of mutualism?
obligate and facultative
what is obligate mutualism?
one species cannot survive without the other
what is an example of an obligate mutualism?
- coral has pulp algae inside, they cannot exist independently
- lichen fungi and algae can exist independently
what is a facultative mutualism?
both species exist independently
what is an example of facultative mutualism?
ants living on acacias
what are acacias?
trees in the savanna that elephants rely on fot nutrients
what are the two acacia species?
acacia drepanolobium and acacia millifera
what did experiments on acacia, ants and elephants reveal?
in the absence of ants, elephant population increased and acacia tree population decreased
conclusion from experiment: ‘Do ants protect acacia drepanolobium from elephants?’
- Yes, elephants avoid acaia drep in ants presence
- they avoid because of ants not because of bad taste
- Yes, having ants saves acacia drep from elephant damage
