Lecture 21 Flashcards
T/F mutualism is the same as symbiosis
false
they are not the same
mutualism is the benefit of both species and symbiosis is that they live together
what is nutritional mutualism
plants that depend on mycorrhizal fungi for their nutrients such as C or P
bacteria that fix Nitrogen for plants to use
what is defensive mutualism
ants protect the plants from other herbivores in exchange for food or housing/shelter
- cleaner fish and client fish - exchange parasite removal for food
what is dispersal mutualisms
animals disperse seeds for the plants to increase reproduction and diversity for the exchange of food (animals eat fruits with seeds)
- animals act as pollinators in exchange for food
what is an example of mutualism between humans and animals
honeyguides eat bees wax and they know where the bees nests are but can’t access them
the honeyguides make loud noises so that the humans can get to the nest and take the honey while the birds can eat the wax
how would u change the Lotka Volterra model of interspecific competition to model mutualism
instead of minus signs between N/K and alpha term - change it to a positive
- but this creates an issue = unbounded exponential growth
what limits the population growth of mutualists
- strong intra-specific compeition
- a third species such as a predator or competitor
- diminishing returns to mutualism as the pop grows - (small pop = mutualism, large pop = no mutual)
invasional meltdown
when 2 invasive species enter a new area, they both help the spread of one another - increasing the disruption and negative impacts
- native seed-dispersing ants move seeds to nests and eat, and disperse the seeds in favourable locations
the invasive seed-dispersing ants may ignore the seeds, eat them and disperse them in unfavourable locations, etc
explain the interaction between cleaner fish and client fish
cleaner fish feed on ectoparasites that live inside the bodies of the client fish
the cleaner fish receives food
and the client’s fish receives parasite-cleaning
- the cleaner fish usually go to territories that clients visit to exchange interactions
- when the lab removes cleaner fish from an area, there are more parasites in the client’s fish
T/F the presence of the cleaner fish in reefs affect the species diversity of other fish
true
- the more cleaner fish = less parasites = more species diversity
explain darwins orchid
has a very long nectar spur
darwin predicted that there must be a pollinator out there that has a very long mouthpart - it was discovered in 1903
= reciprocal adaption/coevolution between flowers and insects
- NS favours flies that have long tongues and plants with longer tubes bc the flowers have more nectar and the flies can receive more nectar
explain bacterial endosymbionts in aphids
aphids feed on sap but it has poor AA
inside aphids, they have bacteria that provide the aphids with the necessary AA
T/F endosymbiotic bacteria has large genomes
false
they have small genomes
- they lose genes they no longer need bc the host has a new way of living
- if an aphid gets AA from another source, the bacteria is not needed and it will stop producing AA for the insect
T/F mutualisms are horizontally transmitted
true
not inherited from parents but developed from the environment or other individuals
T/F mutualisms are usually one-to-one
false
they are usually many to many
