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BIODIVERSITY
“The first animal species to go are the big, slow, the
tasty, and those with valuable parts such as tusks and
skins.” Edward O. Wilson- biodiversity expert
Chapter 14 APES
What is Biodiversity?
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Variety & complexity of life
Genetic diversity- measure of
the variety of different versions
of genes within a species
Species diversity- number of
different kinds of organisms
within communities or
ecosystems.
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Species diversity takes into
account abundance of
species also; “evenness”
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Species “richness”- # of
species in a biological
community or a sample.
Genetic Diversity of Cattle
Calculating Biodiversity
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Ecological diversityassesses the richness
and complexity of
community (including # of
niches, trophic levels,
productivity, nutrient
recycling etc.)
Will calculate this by
Simpson’s Index and
Shannon-Weiner
Diversity Index (related to
uncertainty)
High Species Diversity- complex
community
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High diversity =
complex community,
increased species
interactions, more
energy transfer, high
productivity
 High diversity= high
uncertainty
 Low diversity=?
Biodiversity of the Parking Lot
Discussion questions
 1.How
are diversity (H), species richness
(N), and abundance (frequency f) related?
 2. How are diversity (H) and evenness (J)
related?
 3.What is the relationship between Island
size, richness, diversity, and population
size?
 4. How does this activity demonstrate the
theory of Island Biogeography?
Productivity
How many species are there?
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1.8 million identified
Actual # of species is
probably higher. More
like 3-50 million that have
yet to be discovered.
70% of all known species
are invertebrates
10-15% of all species live
in N. America
Greatest biodiversity
centers are Rainforest &
Coral Reefs
How do we benefit from
biodiversity?
Food
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Many countries have wide
variety of food items that are
not available/cultivated world
wide
Could increase genetic pool
of domestic crop genes.
Indonesia uses 250 edible
fruits, only 43 have been
cultivated widely.
Overgrazing, forest clearing
for unsustainable agriculture
are destroying potential
natural food sources before
they can be identified.
Mangosteen from Indonesia
supposedly the best tasting fruit…
but only found in tropical regionsnot harvested and shipped
overseas for profit. Is that good or
bad?
How do we benefit from
biodiversity?
2. Drugs & Medicine
 Pharmaceuticals made from plants,
animals, & microbes from developing
world have value of $30 billion/year.
 “Biopiracy”- materials/ideas from
developing countries are used but
people not compensated.
 EX: Vinblastine & vincristine from
Madagascar periwinkle are strong
anticancer drugs. The total value of the
crop is $15 million/year, Madagascar
gets little profit.
 Some companies (ex: Merck) pay
scientists to find new organisms.
INBIO pays locals to help find & test
new species.
 Selling data & specimens will finance
scientific work and nature protection.
How do we benefit from
biodiversity?
3.
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Ecological Benefits
Nature maintains ecological
cycles (nitrogen, water, etc)
Genetic library
Some species recover quicker
from disturbance if area was
biodiverse to begin with.
Removing one species greatly
affects all others which could
affect us
EX: removal of wolves in
Yellowstone led to increased
herbivore populations that
competed with livestock and
changed ecosystem.
EX: Insects pests are kept in
balance by other insects and
animals. If they are goneharmful insect populations will
rise.
How do we benefit from
biodiversity?
4.
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Aesthetic & Cultural Benefits
Hunting, fishing, camping,
hiking, wildlife watching, skiing
are based on nature.
Contact with nature can be
psychologically & emotionally
restorative
$104 million spent on wildlife
recreation
Ecotourism is good form of
sustainable economic
development
Existence value- just knowing
it’s there is reason to protect
Religious groups say to protect
God’s creation.
What Threatens Biodiversity?
Natural Causes of
Extinction
 Mass extinctions
due to climate
change from
asteroid impacts
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Ex: Cretaceousdinosaurs & 50% of
existing life died;
Permian- 2/3 of all
marine life died
What Threatens Biodiversity?
Human-Caused
 Some say 1/3-2/3 of
all current species
will be extinct by
middle of this
century. Maybe
considered “6th
extinction” but
caused by humans
not asteroids!
2.
Is this what we
have to look
forward to?
Human Caused
Reductions in Biodiversity
A. Habitat Destruction
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Biggest reason for current
extinctions
Habitat fragmentation
prevents individuals from
finding each other during
breeding seasons
Small pop. Not enough
breeding adults to keep
genetic diversity
Eliminate prominent and
obscure populations
Human Caused Reductions in
Biodiversity
B. Hunting & Fishing
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Overharvesting depletes population &
causes extinctions
EX: passenger pigeon most abundant
bird in world but hunted to extinction in
1900.
EX: Bison killed by U.S. Army to
deprive native people of food, clothing,
shelter so they would have to live on
reservations.
EX: Whales for food, blubber, etc. As
fishing technology improved, whale
population declined. International
Whaling Commission has had positive
effects on whale population- prohibiting
whaling.
Now that population has increased,
should cultural whaling be allowed?
13 out of 17 principal fishing zones are
now commercially exhausted or in
steep decline. Cod industry crashed in
1980’s & 90’s putting 20,000 people
out of work.
See “What can you do?” pg 291 for
other species of endangered seafood
Human Caused Reductions in
Biodiversity
C. Commercial Products & Live
Specimens
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Smuggling of live animals or
animal products is big business.
Developing countries (Asia, Africa,
Latin America) are biggest
exporters
Developed countries (Europe, N.
America, and China) are biggest
importers
Japan, Taiwan and Hong Kong buy
¾ of all cat and snake skins
Europeans buy ¾ of live birds
US imports 99% of live cacti and
75% of orchids
50 animals are caught or killed for
every one that makes it to market.
Ex: Rhinos
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Between 1960 and 1980
population decreased from
100,000 to 3,000.
$28,000 per kg of horn
Use horn for medicinemade from keratin like hair.
Testing has not shown any
medicinal value.
Make dagger handlesolder, larger dagger
handles are more
prestigious ($1,000)
Ex: Birds
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Large birds are too
obvious
Most birds smuggled
in as eggs
Use vests under
clothing to incubate
eggs
Mortality rate very high
Hyacinth macaw goes
for $10,000
Ex: Elephants
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Shows complexity of wildlife trade
Ivory tusks= $100 per kg
1.3 million elephants in 1980; 10
years later only ½ that number.
1989 ivory trade banned.
Pop. have increased greatly
Herds must be thinned to keep
them from destroying habitat.
Ivory from these animals is sold &
money used to compensate people
whose villages are destroyed by
elephant pop. And $ used for
conservation purposes.
Should this sale of ivory be
allowed?
Human Caused Reductions in
Biodiversity
D. Predator and Pest Control
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Many wild animals killed, trapped,
poisoned because they threaten
people, livestock or crops
• Ex: coyotes, bobcats, prairie dogs
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Some killed unintentionally by
eating prey that’s been poisoned
(rodents)
Some killed for sport
Animal Damage Control Program
kills 700,000 animals (100,000 are
coyotes) to prevent competition or
predation on livestock.
Animal protectors say this is cruel
and mostly ineffective- encourage
ranchers to find less destructive
ways to protect livestock (using
herders, guard dogs, fencing)
Human Caused Reductions in
Biodiversity
E. Exotic/invasive species
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One of the greatest threats
to biodiversity
Ex: zebra mussel, kudzu,
purple loosestrife, Asian
long-horned beetle, adelgid
Species from US have
invaded other countries too
EX: Leidy’s comb jellyfish
outcompete organisms in
Black Sea; Bristle worms
taking over coast of Poland
Human Caused Reductions in
Biodiversity
F.
Diseases
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1904 shipment of fungusinfected Chestnut tree
seedlings shipped from
China.
Caused Chestnut tree
blight- reduced population
almost to extinction
Chestnut was a very
important, valuable cropit sprouted quickly, nuts
provided food for many
animals, rot resistant so
good for building
Blight canker on tree- scientists
looking for blight resistant genes so
can breed trees that will resist
disease.
Human Caused Reductions in
Biodiversity
G.
Pollution
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DDT used in 1950’s as
pesticide accumulated in
aquatic ecosystems, fish
eaten by eagles, eagles
become poisoned, weakens
eggshells, shells break,
babies die, population
declines.
Lead from spent shotgun
shells ingested by bottom
feeding waterfowl, store lead
shot in gizzard instead of
stones, lead builds in body,
paralysis, muscle atrophy,
tremors, listlessness, bile
stained feces are common
symptoms- what would
happen to a hunter that ate
these birds?
Trumpeter swans are especially
vulnerable- above- foraging bird
Lead
shot has
been
banned
since
2001.
Below- dead swan from lead
poisoning
Human Caused Reductions in
Biodiversity
H. Genetic Assimilation
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When rare/endangered
species interbreed with
closely related species that
are more numerous it dilutes
gene pool
Hybridized timber wolves
mate with coyotes or
domestic dogs- it introduces
foreign genes into an
already dangerously small
gene pool & reduces
possibility of purebreds to
mate.
ENDANGERED SPECIES
MANAGEMENT &
BIODIVERSITY
PROTECTION
Hunting & Fishing Laws
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In 1870’s animals not
protected because people
thought there would be plenty
to go around. (Bison went
from 6 million to few hundred
during this time)
H & F laws enacted in 1890’s
in most states
Restored habitat, planted
food crops, etc.
Mainly protected “game”
animals
Caused increase in many
species including deer, bison,
wild turkeys
Endangered Species Act (ESA)
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Established in 1973
Identify & protect all endangered
species
Endangered- verge of extinction
Threatened- likely to become
endangered locally (might not be
threatened throughout range) ex:
grizzly bear, bald eagles
Vulnerable- naturally rare, locally
depleted, may be put on list
According to ESA, one cannot
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harass, harm, pursue, hunt, shoot,
trap, kill, capture, collect either
accidentally or on purpose
Import or export in US
Posses, sell, transport, or ship any
endangered species, its parts, or
anything made from its parts.
Endangered Species Act (ESA)
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1. US Fish and Wildlife must
compile a list of endangered &
threatened species
2.Endangered & threatened
sp. May not be caught, killed,
sold or traded.
3.federal gov. may not carry
out any project to further
jeopardize any species.
4.USFWS must prepare a
species recovery plan for each
endangered & threatened
species.
Endangered Species Act
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Problems:
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Slow process from initial
petition to final determination
Limited funding
Political pressure
Listing moratoria
Changing administrative
policies
Many classified as “warranted, but
precluded” for lack of funds or
local support. 18 species have
gone extinct waiting for
protection.
Preserving land is a better
approach.
Many species are indicator
species
Recovery Plans
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Must be submitted by Fish and
Wildlife Services for all species
listed as endangered.
Must show how populations will be
rebuilt to sustainable levels
Takes long time due to cost and
politics so habitat is usually
destroyed in planning process
$13 million on larger species of
mammals only $5 million on 137
invertebrates and 532 plants put
together.
Funding often based on emotions
& politics vs. biology
Success stories
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American alligator, Bald Eagle,
Peregrine falcon
Recovery Plans
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Opponents of ESA
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ESA was overridden in
1978 when Tellico Dam
built in TN, threatened snail
darter fish.
$33 billion industry
hindered when old-growth
forests are preserved for
northern spotted owl. By
protecting the owl we are
protecting lots of other
species.
Private Land and Critical Habitat
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If land had end. species on it, it
must be protected.
Cannot use or sell land
Many private owners resent
this and will “shoot, shovel,
and shut up” or ask for
compensation for lost value
due to ESA regulations.
Habitat Conservation Plans
(HCP’s)- land owner allowed to
harvest resources or build as
long as species benefits
overall.
Reauthorizing the Endangered
Species Act
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Expired in 1992
Opponents- see it as plot to take
away private land, puts plants &
animals before people
Supporters- essential to protecting
nature and maintaining viability of
planet
2 Proposals
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Environmentalists- want protection
of habitat not just individual
species; require deadlines; HCP’s
reviewed by scientists; increase
penalties
Opposers- include all individuals
with vested interest in area; take
cheapest route to save species; no
consultation needed from scientists
Minimum Viable Populations
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If population is too small,
genetic diversity may not be
great enough to keep a healthy
population going.
Island biogeographypopulation can decline
catastrophically due to
environmental change or
genetic problems when
confined to limited geographic
ranges (EO Wilson & RH
MacArthur)
Leads to inbreeding which
makes species weaker.
Occurring with cheetahs &
grizzly bears
Theory of Island Biogeography
 Communities
on large island tend to have
more species.
 The # found is determined by a balance
btwn immigration and extinction
 2 features affect these rates
 1. island size
 2. distance from the nearest mainland
 Fast Fact: 90%loss of habitat causes extinction
of 50% of species on the island
Habitat Protection
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Are we spending more $
on species whose genetic
diversity is already so
low, it’s already doomed?
If we breed animals in
zoos & release them, will
we have a habitat to
release them into?
By protecting habitat we
protect many species not
just one.
International Wildlife Treaties
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Convention on
International Trade in
Endangered Species
(CITES)
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Est. in 1975
Worldwide ban and
protection of end. Flora &
fauna
Developing countries have
more pressing problems
than protecting species
Difficult to keep track of
smuggling- law
enforcement lax.
Captive Breeding & Species
Survival Plans
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Many species caught from wild
and put in zoos- 80% die in transit.
Now, more species are being
produced from breeding in
captivity.
Bats, whales, reptiles will not
breed in cages
Zoos could provide money &
resources (radios, training, etc) to
native habitats to preserve animals
in native areas.
Would you favor saving disease
organisms, parasites, or vermin or
should we use our limited
resources to save only beautiful,
interesting, useful organisms?
Species Survival Plan- move
animals between zoos for mating
to keep good genetic diversity
Botanical Gardens & Germ Plasm
Banks
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Botanical gardens are
like zoos for plants
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Germ Plasm Banksare “sperm banks” for
plants and animals.
Keep seed or
sperm/egg viable in
case populations
become
endangered/extinct.
Characteristics of species which make them prone to
extinction
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Characteristic:
Low reproductive rate (K
strategist)
Specialized niche
Narrow distribution
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Feeds @ high trophic level
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Fixed migratory patterns
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Rare
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Commercially valuable
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Large territorities
Example:
Blue whale, panda, rhinoceros
Blue whale, panda, everglades
kite
Many island species, elephant
seal, desert pupfish
Bengal tiger, bald eagle, grizzly
bear
Blue whale, whooping crane, sea
turtles
Many island species, African
violet, orchids
Snow leopard, tiger, elephant,
rhinoceros, rare plants
California condor, grizzly bear,
Florida panther
Private Organizations
 Many private organizations work to protect
species worldwide, often more effectively than
government agencies.
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World Wildlife Fund – sustainable use of resources
and wildlife protection
Nature Conservancy – has purchased land to turn
into nature preserves in 29 countries
Conservation International – identifies biodiversity
hot spots