Transcript Topic 2 - Holy Cross Collegiate

Biological Diversity and
Survival
Topic 2
Habitat and Lifestyle
Habitat and Lifestyle
Like humans,
plants and animals
have variations that
allow them to adapt
and survive more
effectively than
other plants and
animals in the same
ecosystem
The Niche: What Makes
an Organism Special?
Niche:
– The role or characteristic
activity that is undertaken by
an organism in an ecosystem;
one organism may fill several
different niches
– An organism’s niche includes
two parts:
• Where an organism lives
(ie. its Habitat)
• What an organism does
(ie. its Behaviour)
Environment:
– The area or conditions in
which an organism lives;
sometimes used to refer
exclusively to natural areas on
Earth
The Niche: What Makes
an Organism Special?
Ex. A Poplar Tree
– Absorbs light for
photosynthesis
– Removes carbon dioxide from
the air and releases oxygen
into the air
– Provides food and shelter for a
wide variety of organisms
– Stabilizes the soil from erosion
(wearing away)
– Covers the ground with leaves
in the fall, which returns
nutrients back into the soil
– Removes water and nutrients
from the soil
Variation and
Competition
Competition:
– The struggle among individual organisms for
access to a limited resource, such as food or
territory
– Competition can be between members of the
same species (ie. Intraspecific Competition) or
between member of different species (ie.
Interspecific Competition)
Variation and
Competition
Ex.
– Mule deer and Whitetailed deer compete for
food and variations can
allow one species to
adapt more rapidly to
their environment.
Those animals that are
able to survive will
reproduce more often
and “take over” the
habitat.
– Bighorn Sheep Go Head
To Head
Variation and
Competition
Some animals will avoid competition by
changing their behaviours such as eating
different food sources or hunting at
night rather than during the day
Ex.
– There are a number of Warbler varieties
across Canada and the United States. Each
Warbler variety eats insects, however each
type of Warbler has evolved to have different
eating habits to avoid competition
Variation and
Competition
– Cape May warbler feeds on
insects at the top and tips
of the tree
– Yellow-rumped warblers
feed on insects near the
trunk’s lower branches and
on the ground
– Black-throated green
warblers feed near the
middle of the tree
– Blackburnian warblers feed
from the outer tips from
the middle to the top
– Bay-breasted warblers feed
from the lower half of the
tree away from the tips
The Broad Niche
Biodiversity:
– The number of different types of species that live in one
ecosystem
Biodiversity in Canada
– Canada has very few different types of species (low
biodiversity), however these species have massive numbers
– Ex.
• Caribou herds (Rangifer tarandus),, Wolves (Canis lupus), and
Polar Bears (Ursus maritimus)
The Broad Niche
Broad Niche:
– The roles or characteristic activities filled by a
generalist organism
– Since Canada has such drastic climate changes during
the year the organisms that live here must have a
broad niche
– These ecosystem conditions make it very difficult for
many species to adapt
Generalists
– An organism with generalized requirements and
adaptations that allow it to survive in variable
conditions and depend on a variety of food sources;
generalists tend to have broad niches
Diversity in the Tropics
In the tropics, temperatures
and food supplies are relatively
stable allowing animals to
become specialists
The Amazon has a huge
number of different types of
species (high biodiversity),
however these species have
very low numbers
Ex.
– Some species of Leafhopper
insects are found on only
one tree in the entire
Amazon
Diversity in the Tropics
Specialists:
– A type of organism
that is adapted to
very specific
environments and
having a narrow
niche
Narrow Niches
– A highly specialized
role or characteristic
activity undertaken
by an organism in an
ecosystem
– Cheetah vs gazelle BBC wildlife
Dependencies Between
Species
Many species rely on other species in
order to survive
These relationships are known as
symbiotic relationships
Symbiotic Relationship:
– An interaction between organisms of
different species living in close proximity to
each other in a relationship that lasts over
time
– There are three major types of Symbiotic
relationships
Dependencies Between
Species
–
Mutualism:
–
A symbiotic relationship in
which the organisms of both
species benefit
–
Commensalism:
–
A form of symbiosis in which
one organism benefits, and the
other organism is neither
helped nor harmed
–
Parasitism:
–
A symbiotic relationship in
which one organism, called the
parasite, derives benefit at the
expense of another organism,
called the host
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Nematodes in Gut
Live Diphyllobothrium Latum
during Colonoscopy
Cordyceps: attack of the killer
fungi - Planet Earth Attenborough
Life in theThough
Extreme
you might not think it, life is
found all over the planet no matter how
extreme
Organisms that live in extreme
ecosystems are classified as
Extremophyles (able to live in extreme
ecosystems)
– Halophiles: Live in extremely salty
ecosystems
– Thermophiles: Live in extremely hot
conditions
– Acidophiles: Live in extremely acidic
conditions
– Alkaliphiles: Live in extremely basic
conditions