Download Relationships of Living things

Relationships
of Living things
All living things within an ecosystem
interact in many different ways.
They can….
Collaborate
•Hunt together in
packs
•Stick together for
safety
•Defend each other
against harm
•Huddle for warmth
•Share food supplies
Compete
..Or…
•For food
•For space
•For mates
•For light
•For power/dominance
Whether they are in
or
if the organisms are from the
same species their relationship is known
as….
….and if the organisms are from different
species their relationship is known as…
And a handy general term to describe an
intimate relationship between organisms is…
Let’s look at the different kinds of relationships
between species according to the outcomes for
those species involved…..
What are the possibilities?
One is Harmed
BothGain
One Gains
One Gains
One is
indifferent
3. Allelopathy
1. Predator/Prey
relationship
4. Mutualism
5. Commensalism
2. Parasite/Host
relationship
Let’s begin with a simple food chain….
•Producer
•1o Consumer
•2o Consumer
•3o Consumer
•Herbivore
•1 o Carnivore
•2o Carnivore
..or if we want to look at trophic levels…..
1st
trophic
level
2nd
trophic
level
3rd
trophic
level
4th
trophic
level
….or if we want to look at it terms of predator/prey…
Prey
(rarely
Predator)
Prey &
Predator
Prey &
Predator
Top
Predator
1) Predator/Prey Relationships
This type of relationship is severe as one
organism – the prey - is killed to benefit
the other – the predator. There can be 4
different outcomes for the groups of
predators or prey:
Both predator
and prey die
Predator lives
and prey dies
Predator dies
and prey lives
Both predator
and prey live
Which is the most beneficial to both
organisms?
Each of the four graphs on your worksheet shows one of
these 4 outcomes – can you identify them?
1) Predator/Prey Relationships
Predators:
Prey:
•Usually less abundant
than prey
•Usually more
abundant than
predators
•Compete for prey and so
can adapt to do so better.
For example echolocation
in bats
•Collaborate by hunting in
packs
•Need to defend
themselves can employ
a series of methods;
a)Counter attack
b)Mimicry
c)Camouflage
Some examples…
1) Predator/Prey Relationships
Counter attack:
•Can take a huge variety of forms and can
be adaptations that are physical,
behavioural or physiological
•Aim is to defend prey from predator
•Examples include:
•Horns, antlers
How does this squid
counter attack?
•Offensive smells
•Tough outer shells
•Burrowing
•Speed
•Poisons
Squirts out black ink
to confuse the
predator!!
1) Predator/Prey Relationships
Counter Attack
A female insect protects
her eggs with sharp
crystals. Breathing or
eating these crystals
could be fatal to another
insect. X2,000
1) Predator/Prey Relationships
Mimicry – When organisms copy or imitate
each other. Can be two types:
Mullerian mimicry
Batesian mimicry is
is when poisonous
organisms share the
same warning
patterns or colours.
when the organism is not
poisonous but copies or
mimics the poisonous one.
It is behaving like a fraud.
Examples are the
patterns of black
with yellow or
orange used by frogs,
bees and monarch
butterflies.
Examples are caterpillars
looking like vipers or
octopuses mimic sea snakes
by swimming with equal
number of tentacles in
front as well as behind
them.
1) Predator/Prey Relationships
Camouflage is when an organism hides itself in or
around its surroundings and blends in by taking on a
similar appearance. The organism can do this by using
colour, shape or texture.
Examples include stick insects, pepper moths,
chameleons, (the game ‘Where’s Wally’ works on the
camouflage principle).
Not good camouflages!!
Better!!
2) Parasite/Host Relationships
This common form of symbiosis, consists of one
organism benefiting to the detriment of another.
There are two forms:
Ectoparasitism
Endoparasitism
This is when the
parasite lives
outside the host
body.
This is when the
parasite lives
inside the hosts
body.
Examples
include ticks,
fleas and fungal
skin infections
Examples include
tapeworm, liver
flukes, bacteria
and viruses
2) Parasite/Host Relationships
•Fleas are parasites because they suck
blood from other animals.
•Usually a particular species of flea will
bite a different kind of animal, unless
they get really hungry!
•Their cuticle has to be thick as their
host is always trying to kill them.
•Many bug sprays will kill the adult but
not the eggs, so fleas are hard to get
rid of.
•Note the small eyes. Why don’t they
need good eyesight?
•Their bodies are narrow to fit easily
through hair and fur.
x180
•Fleas can spread disease - the most
famous being the plague or Black Death.
3) Allelopathy
•This is a relationship where one organism directly
hinders or stops the growth of another by releasing
chemicals
•It occurs most often between plants and botanists
initially thought it was simply competition of resources
that allowed one species to dominate an area over
another
•Now, agriculturalists are exploring the possibility of
using allelochemicals as growth regulators and natural
pesticides for crop growing
3) Allelopathy
…or through
the leaves
Plants can release allelochemicals
through the roots...
3) Allelopathy
•Several species of sage (Salvia) use chemicals to inhibit the
growth of other vegetation. Sage is often surrounded by bare
areas separating them from adjacent grasses, they grow into
the bare areas pushing grasses further back. The chemical
that is produced by the sage leaves gives it the quality of a
spice.
•Another example of allelopathy is the production of
flammable oils by eucalyptus trees; the oils promote frequent
fires, which kill seedlings of competitors
4) Mutualism
Mutualism is a form of symbiosis when both
organisms in the relationship benefit. Examples
include:
• Fish swimming together in shoals
•Small fish who clean parasites from the gills of
larger predator fish
•Pollinators and seed dispersers
•Microscopic organisms that help larger herbivores
digest cellulose
4) Mutualism
•Pollinators carry pollen from one plant to another:
•Plant benefits from pollinator (insect or bird) by having
pollen carried to another plant for cross fertilization
•Pollinator benefits from the plant by directly eating the
pollen or by inadvertently taking pollen while feeding on
plants nectar
•Pollen can adapt to increase their chances of hitching a ride
•Pollinators can adapt to collect more pollen
This pollen has a prickly coat that
sticks to insects better than
smooth pollen, this improves its
chances of reaching another
flower. X3,000
Female bees comb pollen between hairs
that grow in rows on their back legs. One
worker may collect millions of pollen
grains in a single trip. The bees feed the
larvae the pollen (as well as the honey
made from nectar). X1,000
4) Mutualism
•Seed dispersers carry seeds away from the plant:
•Plant benefits as it has a chance to reproduce and
spread its species
•Dispersers (usually a bird) benefit as they can eat
the seeds
•Seeds can adapt so they have greater chance of sticking
to their disperser and travelling great distances
Hooks on a burdock seed pod can
attach themselves to passing
animals, including people, who
spread the seed far and wide. x174
Did you know that Velcro was
modelled on these seed hooks and
looks almost the same under the
electron microscope?
5) Commensalism
•This form of symbiosis is usually very hard to
define as scientists don’t always understand
fully the relationships between organisms.
•Examples could include:
•Trees that support other vegetation –
orchid seeds rest on branches and grow
from there
•Soft bodied sea dwelling animals that use
discarded shells to live in
•Clown fish and poisonous anemones
Biological Control
Biological control is when scientists use one
organism to control the population of another by
introducing them in close proximity. What kind of
symbiotic relationship does this exploit?
Examples include:
•The cane toad (1935) introduced to control
sugar pests
•Weevils (1980) to control weeds
•Myxomatosis (1950) to control rabbits
•Calicivirus (1996) to control rabbits
•Moth (1925) to control prickly pear
Successful?
No
Yes
No
Yes
Yes
Biological Control
……an example
Aphids use their proboscis to suck the juices from
leaves. They can be killed by poisons, but some
gardeners prefer to use ladybugs that can eat aphids in
their thousands.
..but…
EM of an aphid x68
Aphid cornicles provide the one defense
system aphids have against ladybugs. When
attacked they squirt a sticky cement which
sticks the ladybug to the leaf and gums up
its wings so it can’t fly away. x250
What is another biological term for this
kind of defence the aphid has against its
predator the ladybug?
Counter
Attack!!
The
End!