Transcript Symbiotic Relationships

Symbiotic
Relationships
Who gets along? Who doesn’t?
Who hurts who?
Species Interactions
5 basic types of interactions of species within an ecosystem.
1. Interspecific competition – When members of two or more
species interact to gain access to the same limited resources.
1. ie: food, light, space
2. Predation – when a member or group of members of one
species feeds directly on another species.
1. Usually animal to animal
2. Rare cases of plants to animal
3. Parasitism – when one species feeds on/in the body of
another species and harms it.
4. Mutualism – interaction of two species when both benefit
from the interaction.
5. Commensalism – interaction of two species when only one
benefits from the interaction and the other is not harmed or
benefited.
Species Interactions
• Interactions have a significant effect on the resources used and the
population of different species within the ecosystem.
– b/c of these interactions the ability to reproduce and or survive is
influenced.
• Natural selection takes place through interactions.
• The most common interaction is competition.
– For limited resources
– Requires one species to have the ability to be more efficient than
another when finding and utilizing resources like food and shelter.
– The role species play in an ecosystem is considered their ecological
niche. (ie: the job they have, how they act towards their environment,
what they do in their environment)
– When species compete for food, shelter, light; their niches overlap.
The more overlap the more intense the competition.
Species Interactions
• Predation (predatory-prey interaction):
– Most consumer species feed off of other consumer
species.
– Herbivores – feed off of plants and other producer
type species.
– Omnivores – feed on plants and other living
consumers.
– Carnivore – feed on other living consumers only
– To survive predators must eat other prey, without they
would die and the evolution of the species can be
stunted.
Species Interactions
Predator/Prey cont.
• Predators – a closer look…
– Methods used to capture prey:
• Herbivores – simply walk, swim or fly to the plant when
needing to eat.
• Carnivores/Omnivores – have moving prey so there are
a few main types of capture to eat.
– 1. Pursuit – run, chase prey until they wear them out or catch up to
capture and eat.
» Usually a single predator after a single prey.
– 2. Ambush – When one or more predators lay in wait or similar
techniques to capture and eat prey
» Hunting is an organized way to ambush prey, seen from lions,
wolves, humans, pack type organisms.
» Camouflage – The predator disguises themselves to ambush the
prey.
– 3. Chemical Warfare – Predators use venom or poison to attack prey
» Venomous snakes and spiders spit on or bite a prey organism
and wait for them to immobilize before eating them.
Species Interactions
Prey – A closer look…
• Evolved/Adapted to avoid predators:
– Being able to move fast, quick reflexes (long legs, strong
muscles)
– Highly developed sense of sight, smell or hearing (large eyes,
ears, nose)
– Avoidance adaptations like shells (turtles), thick bark (giant
sequoia), spines (porcupines), and thorns (rose bushes, cacti)
– Camouflage – being able to blend into their environment so as
not to be easily seen. (the moth, chameleons, cuttlefish)
– Chemical Warfare – discourage predators to eat them
• by having a Warning Coloration… bright colored markings like red, orange,
yellow, blue; all with usually black markings. (some frogs, snakes,
salamanders)
• This lets the predator know that they are poisonous or taste bad and
should not be eaten. (oleander, monarch butterfly)
Species Interactions
Prey cont.
– Foul smelling, gives off a nasty odor when startled or
caught (skunks, skunk cabbage, stinkbugs)
– Irritating – gives off a chemical or needles that irritate
the predator. (bombardier beetle, stinging nettles)
– Mimicry – acting like or looking like an organism that is
poisonous so as not to be eaten (viceroy butterfly looks
like the monarch)
– Living in large groups so as to not to be the one most
likely eaten (schools of fish – tuna; Zebras)
• Usually the one captured and eaten are the sick, old or young of
the group.
Symbiosis
Three types of Symbiotic relationships between
organisms:
– Mutualism – both organisms benefit from the interaction.
– Commensalism – One organism benefits, the other
organism is not harmed or benefits from the interaction.
– Parasitism – One organism benefits, the other organism is
harmed, but may not always die during the interaction.
Looking at pics