Loading presentation...

Present Remotely

Send the link below via email or IM

Copy

Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.

DeleteCancel

Make your likes visible on Facebook?

Connect your Facebook account to Prezi and let your likes appear on your timeline.
You can change this under Settings & Account at any time.

No, thanks

Biodiversity

No description
by

Sonia Bawa

on 16 January 2015

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Biodiversity

Biodiversity
Do Now
What is biodiversity?
Biodiversity
Variety of:
Species
Recall that a species consists of organisms that can interbreed and produce fertile offspring.
Sometimes also referred to as BIOLOGICAL DIVERSITY
natural services
(Functional Diversity)
ecosystems
(Ecosystem Diversity)
genes
(Genetic Diversity)
species
(Species Diversity)
*Biodiversity is considered to be a RENEWABLE RESOURCE
Possible Species:
4-100 million
Known Species:
1.8 million
Insects:
1 million
Vertebrates:
45,000
Plants:
270,000
*Key takeaway: General order
What does biodiversity do for us?
Think about what we have learned so far.
What do we do for biodiversity?
How did life get to be so diverse?
Through evolution via Natural Selection!
Who proposed this idea?
Charles Darwin
Natural Selection
2. Random mutation in DNA Adaptation
1. Limited Resources Competition
3. Reproduce to spread adaptation to offspring
Scientists propose that all organisms evolved from one species.
With a partner, using what you just learned, explain how it is possible that all of the species around us today could come from one species.
Who is the most powerful species on Earth?
Humans!
How did humans become so powerful?
1. Opposable thumbs
2. Upright structure
3. Complex brain
Although organisms can evolve, this process takes time.
Unfortunately, conditions on Earth are changing so rapidly, that there is not enough time for many species to evolve.
What species is responsible for the drastically changing conditions?
Humans!
How are humans affecting biodiversity?
1. Increasing rate of speciation
2. Causing premature extinction of species
Speciation
New species being formed
(through Natural Selection)
Most Common Method of Speciation (2 Steps)
1. Geographic isolation
2. Reproductive Isolation
Geographic Isolation
Groups of the same species get physically isolated for long periods of time.
Potential Causes
1. Physical barrier
(mountain, body of water, road)
2. Volcanic eruption or earthquake
3. Organisms being swept away by wind or water
Now groups of the same species have been physically separated.
Also, it is likely that the environments of each group is different.
So, in each environment, different traits will be beneficial.
As Natural Selection occurs in each environment, the two groups will end up evolving so differently that the groups would no longer be able to breed with each other if they were ever reconnected.
The groups that have been separated cannot mate.
REPRODUCTIVE
ISOLATION

Extinction
An entire species dies out
Endemic Species
A species found only in one area
Usually in:
Islands
Tropical Rainforests
*Because these species are so specialized, they are more likely to go
EXTINCT
Costa Rica's Golden Toad
Poster species to bring awareness about how climate change is causing an increase in extinction.
2 Major Groups of Extinction
1. Background Extinction
Species disappear at a low rate (1-5 species/million yrs)
2. Mass Extinction
Huge group of species get wiped out
Mass Extinctions
There have been about
3-5 mass extinctions
in Earth's history.
Although mass extinctions take away large groups of species, this process provides
room and resources for completely new species to arise.
Background Extinction
Species are going extinct all the time.
However new species are also being created all of the time.
'BACKGROUND EXTINCTION causes limited damage to an ecosystem.'
Mass Extinction
Dinosaurs
Elephant Bird
Wooly Mammoth
Since Background extinction is a long process
Other organisms affected have time to adjust/evolve as a species
Species Diversity
Species Richness
Species Evenness
- number of species
- number of members of each species
Usually...
If
species richness
is
HIGH
,
species evenness
is
LOW
AND...
If
species richness
is
LOW
,
species evenness
is
HIGH
Tropical regions have high species richness.
Species Richness
and
Species Evenness
depend on
Geographical location

Generally, as you get further from the equator, species richness decreases while species evenness increases.
What's better?
Species Richness or Species Evenness?
Scientists believe that
SPECIES RICHNESS
is better
Higher species richness,
Higher
productivity
More
stable
and
sustainable
ecosystems
The more species, the more likely it is for some species to withstand natural disasters
Why are species rich ecosystems more stable and sustainable?
Species tend to be
highly specialized
All have different
niches
(rely on different
resources
)
If something happens to 1 resource, not every species will be harmed
As a WHOLE, species richness is more sustainable
This is the opposite of ecosystems with high species evenness.
Within a species rich ecosystem, there are species with different niches.
Two General Groups:
Generalist
Specialist
Less specialized
More specialized
What's better?
Generalist or Specialized?
When conditions are good/stable,
specialists
have the advantage.
Less competition
When conditions are bad/unstable,
generalists
have the advantage
Acclimate better
Cockroaches
Over 350 million years old!
How did they survive?
Very versatile generalist species.
Can eat almost anything.
Reproduce a lot and quickly.
Evade predators with senses.
Go for long periods without food.
Biological Hotspots
Areas that contain many endemic species
Generally...
The organisms that will survive drastically changing environmental conditions will be those that are most...
ADAPTABLE!
If there is another mass extinction, which organisms would be the ones that survive?
To understand this, we need to understand a bit more about species diversity
Importance of Biodiversity
Direct economic value
Indirect economic value
Aesthetic and scientific value
We depend on plants and animals for:
food
,
clothing
,
energy
,
medicine
, and
shelter
We depend on plants and animals for:
air purification
,
water purification
,
flood protection
,
waste detoxification and removal
, and
climate regulation
Humans Tend to Threaten Biodiversity
Overexploitation
Habitat Loss
Habitat Fragmentation
Pollution
Biological Magnification
Acid Precipitation
Eutrophication
Humans also do some good things for biodiversity!
CONSERVATION BIOLOGY
Protected Areas
National Parks and Nature Reserves
Internationally...
Biosphere Reserves and World Heritage
Costa Rica's megareserves
In U.S....
Funding conservation of
BIOLOGICAL HOT SPOTS
Corridors between habitat fragments
Protection Biodiversity
Restoring Ecosystems
Bioremediation
Biological Augmentation
Legally Protecting Biodiversity
In a given ecosystem, species can be classified into
5 general groups
according to their
NICHES
Native Species
Nonnative Species
Indicator Species
Keystone Species
Foundation Species
ONE species is not limited to ONE role
Native Species
"Species that normally live and thrive in a particular ecosystem"
AKA Indigenous Species
Presence of a species in a given area is
NATURAL
and not due to human activity
Nonnative Species
Invasive, alien, or exotic species
Migration
Accidental Introduction
Deliberate Introduction
Nonnative species can be good or bad...
E.g. crops, chickens, cattle, and some fish
Some domesticated species provide us with food:
Some nonnative species can push native species into extinction
E.g. killer bees
Indicator Species
Species that provide early warning of ecosystem or community destruction
Indicator Species
Trout
Only live in
CLEAN WATER
with lots of
DISSOLVED OXYGEN
Trout have a very narrow range of conditions that they live in.
Although all fish benefit from clean water and lots of oxygen,
Many other fish can tolerate more variable conditions.
However, if we notice that trout are not there, scientists can monitor water quality to make sure that conditions do not get too bad.
Birds and Butterflies
Indicator Species
Quickly/Easily affected
by environmental changes such as
Habitat Loss
or
Habitat Fragmentation
In general...
Indicator Species are
Biological Alarms
that are important so we can
limit damage to species
to prevent...
ENDANGERMENT

or
EXTINCTION
Amphibians
Indicator Species
(frogs, toads, salamanders)
Activity
Keystone Species
A species that has a very
LARGE
effect on
MANY
other species in the ecosystem
Removal or extinction of a Keystone Species
would have
DRASTIC EFFECTS
on the community it belongs to.
If missing...
Some Keystone Roles...
Pollination
Top Predators
Maintain diversity of flowering plants
Control populations of species lower on the food chain
Because Keystone Species have such a great effect on their communities,
scientists especially focus on protecting them
.
Foundation Species
In the process of using their environment to their own advantage, foundation species benefit other species
Elephants pushing over trees
Beavers building dams
Keystone Species vs. Foundation Species
Major Differences:
Keystone Species
have a more
DIRECT
effect on other species
Foundation Species
have an
INDIRECT
effect on other species
Human Effect on Biodiversity
Overhunting/ Poaching
Bats and birds spreading seeds
Full transcript