Download The Loss of Biodiversity

The Loss of Biodiversity
Loss of Biodiversity
• According to The
International Union for
Conservation of Nature
(IUCN) many animal and
plant species are at a
tipping point
• At threat of extinction are
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–
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1 out of 8 birds
1 out of 4 mammals
1 out of 4 conifers
1 out of 3 amphibians
6 out of 7 marine turtles
Loss of Biodiversity
• Why should we care
about this loss in
biodiversity?
• There are important
biological resources
that are being lost
• Food, resources,
medicines are being lost
Loss of Biodiversity
• Also abiotic resources
are being lost
• Many biogeochemical
cycles are being
threatened
• Water purification is
being lost
• The ability to capture
and store energy is
being lost
Extinction
• There are several terms
that are thrown around
when it comes to the
loss of biodiversity
• Not all of the terms are
used in the correct way
• It is important to define
the terms in the way
that define what they
are
Extinction
• A species that happens
to be at risk of
disappearing if their
current trend continues
is defined as
threatened
• A loss of a population in
a local area is called a
extirpation
• A loss of a species
completely is called an
extinction
How Fast?
• Many scientists have
tried to quantify the
rate with which we are
losing organisms to
extinctions
• The past and future
estimates are rough due
to the effort it takes to
get data
How Fast?
• However, the difference
between past and present
models is startling
• There is around a one
hundred times greater
extinction rate now than
there is any evidence in
the past for many
categories of species
• The projections for the
future see no halt to this
pattern
How Fast?
• Realizing this, humans
have started to try to
slow the incredible rate of
extinctions
• One of the first and most
effective was the
Endangered Species Act
of 1973
• This placed restrictions on
development in areas
with endangered species,
sale and housing of
endangered species and
money allotted to help
preserve these species
Video
• http://www.cbsnews.co
m/news/theendangered-speciesact-turns-40/
The Threats
• There are four main
threats to species
• The largest threat is
human development and
habitat loss
• The second largest threat
to species diversity is
invasive species
• Overharvesting and
bycatch is the third
largest threat to species
diversity
The Threats
• The fourth threat to
species diversity is
pollution
• This is when nonnative,
harmful or deadly
chemicals are
introduced to an
ecosystem
• This can destroy
ecosystems
Pollution
• However pollution does
not affect only species
that live in a polluted
area
• Many pollutants cannot
be removed from a
system
• They can become
concentrated as they
travel to higher trophic
levels
Pollution
• Biomagnification is the
process of chemicals
being concentrated as
they travel up the food
web
• Organisms that have low
levels of pollutants are
eaten by organisms that
acquire small does from
many of their food
sources
• The pollutants pile up
faster than organisms can
rid them from their body
Pollution
https://www.youtube.com/watch?v=v2EtxYxEK
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http://www.cbsnews.com/news/after-ddtscourge-bald-eagles-return-to-catalina/
• A very famous case of
this was DDT and Bald
Eagles
• DDT was traveling from
insects/ fish and ending
up in dangerous levels
in bald eagles
• The DDT was causing
the eggs of bald eagles
to become brittle and
break when an eagle
would nest on them