Genetic Diversity

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Chapter 10
BIODIVERSITY
What is biodiversity?
Bio =
Diversity = Variety
BIODIVERSITY is short for… BIOLOGICAL DIVERSITY
Some areas contain an extraordinary variety of
species (more biodiversity)…
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Tropical rain forests
Islands
Coral reefs
Coastal areas
aerial view of Fiji Islands and coral reefs
1.6 million – “known” species
on Earth
most of which are INSECTS
What determines
whether a
species is “known”?
when it is collected
and described scientifically
(given a scientific name)
Where do unknown species exist?
• remote wildernesses
• deep in the oceans – hydrothermal vents
• cities…
One-of-a-Kind Find…
Patch-nosed Salamander
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2007 - Bill Peterman found a small salamander
2” in length
found in Stephens County, Georgia
smallest salamander species ever found in US
2009 - identified as a new species
Levels of Biodiversity
• Species Diversity
• Ecosystem Diversity
• Genetic Diversity
Species Diversity
refers to….the number of different species in an area
Velvet Worm
Bromeliad
Indian Spectacled Monkey
Ecosystem Diversity
refers to… the variety of habitats and
communities and within ecosystems
Namib Desert, Africa
Coral Reef, Tropical Ocean
Genetic Diversity
refers to…. all the genes contained within
the members of a population
Gene - a segment of DNA that codes for a specific trait
The greater the
genetic diversity
the healthier
the species !!!
The word BIODIVERSITY most often refers to….
Species Biodiversity
Benefits of Biodiversity
Biodiveristy can affect…..
1. the stability of ecosystems
2. the sustainability of populations
Keystone Species….
species that are so important
to the functioning of an
ecosystem that if they
disappear the ecosystem
changes dramatically
California Sea Otter
• In 1800’s - hunted for their fur
• By 1900’s - population was
decimated and close to extinction
• with the near extinction of the sea
otter, sea urchins multiplied and
ate the kelp, altering the ecosystem
and affecting many species of fish
and invertebrates
Small, Isolated Populations are Less Likely to Survive Environmental
Changes
Island Nation of Tuvalu – chain of small islands in South Pacific
• Average height above sea level - 6 feet
• Highest point above sea level - 15 feet
Global Warming is threatening ……
• 1 native species of endodontid snail
• 4 native species of charopid snail
• 1 native species of reptile
Genetic Diversity
within a population
is critical to
species survival ….
Genetic Diversity Florida Panther
1970’s – estimated 20 panthers
2011 – estimated 100-160 panthers
these 100-160 panthers have limited genetic diversity –
having come from an original group of 20
FLORIDA PANTHER
http://www.youtube.com/watch?v=qznv5I21MSA
Genetic Diversity Amur Leopard
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classified as CRITICALLY ENDANGERED
amongst the rarest animals in the world – native to Russia
only 30 to 40 individuals surviving
this species may already be doomed - despite any conservation efforts
AMUR LEOPARD - http://www.arkive.org/amur-leopard/pantherapardus-orientalis/video-or00.html
Genetic Diversity –
Cheetah
Cheetah…
• Early 1900’s - estimated 100,000 in Africa + Asia
• Today – estimated 7,600 in Africa + Asia
Reasons for the decline …
• habitat loss
• loss of prey
• competition with other predators
• conflict with man
• does not do well in parks or in captive breeding
CHEETAH - http://www.youtube.com/watch?v=tz1rGmY2c_s
Cheetah’s Range
BIODIVERSITY ….
• medicine, food, clothing, building + industrial materials …
• purifies water, recycles nutrients, makes the soil fertile…
• camping, pets, photography, wildlife, ecotourism
Foods from the….
Americas
Africa, Central Asia
and the Near East
Far East, India
and Pacific Islands
Corn/Maize
Tomato
Beans
Peanut
Potato
Sweet potato
Avocado
Pumpkin
Pineapple
Cocoa
Vanilla
Peppers
Wheat
Sesame
Chickpeas
Figs
Lentil
Carrot
Pea
Okra
Date
Walnut
Coffee
Cow
Goat
Pig
Sheep
Soybeans
Rice
Banana
Coconut
Lemon
Lime
Orange
Cucumber
Eggplant
Turnip
Tea
Black
Pepper
Chicken
Hybrids
• most new crop varieties are hybrids….
developed by combining genetic material
from more than one population
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Grapefruit
Mandarin orange
Tangelo
Loganberry
Rutabaga
Ecotourism
• A form of tourism that supports the conservation and
sustainable development of ecologically unique areas
Cruise Ship in
Antarctica
Section 2 – Biodiversity at Risk
EXTINCTION….
when all members
of a species die
MASS EXTINCTION….
the extinction of many
species in a relatively
short period of time
Some scientists warn that
we are in the midst of
another mass extinction.
Some scientists estimate that as
many as 20,000 extinctions
are occurring each year.
The rate of extinction has
increased by a multiple of
50 since the 1800s.
It is believed that between
1800 and 2100 (300 years)
25% of all species on Earth
may become extinct.
Dodo Bird – extinct 1690’s
Why did the Dodo
become extinct?
it was flightless,
had no fear of man,
and
was hunted for food
How will the current mass extinction be
different from those in the past?
HUMANS are the primary cause
Cockroaches and rats are not likely to
become extinct. Why?
Species with small populations in
limited areas can easily become
extinct. Why?
Ivory Billed Woodpecker
extinct 1960’s
Other factors that put species at risk….
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species that migrate
species that need large habitats
species that need special habitats
species that are exploited by humans
Endangered species - is likely to become extinct if
protective measures are not taken immediately
Threatened species – has a declining population and is
likely to become endangered if it is not protected
In 1967 - the Bald Eagle placed on
Endangered Species List
In 2007 - removed from the list
because populations
recovered sufficiently
How do humans cause extinctions?
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habitat destruction…
habitat fragmentation….
habitat degradation….
invasive/exotic species….
harvesting, hunting and poaching….
pollution….
What are the causes of
species loss (extinction)…
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Habitat Loss
Exotic Species
Exotic Pet Trade
Poaching
Pollution
Global Climate Change
Population Growth
Over Consumption
Habitat loss…including…
Habitat Destruction – to demolish or destroy
Habitat Fragmentation – to break into pieces
Habitat Degradation – to deteriorate
Exotic Species….
species that are not native/endemic to an area
EXOTICS threaten native species..…
• by competing with them
• native species have no natural defenses against the exotics
also known as…..
alien, foreign, invasive,
introduced species
Exotic Pet Trade …
trade involving any animal that is not native to an area
the state of Florida is experiencing problems with many exotics – Iguanas,
Burmese Pythons, Ferrel Hogs, Monitor Lizards and Gambian Pouch Rats
Why are species harvested and sold?
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pets – python, parakeets, lizards,….
houseplants – orchid, bromeliad, pothos,…
wood/building materials – teak, bamboo, cedar,…
food – shark fin soup, mangoes, coconut,…
herbal medicine – rhino horn, bear gall bladder,….
Poaching …
the unlawful hunting, fishing, harvesting or trade of wildlife
Rhino are killed for their horn which is used in traditional
Chinese medicine and in handles in expensive daggers
Black Rhino
Pollution…
any contamination of
air, water or soil
What types of pollution are
making their way into
food webs? pesticides,
cleaning agents, drugs,
other chemicals
How do these get into the
environment?
POLLUTION ….
was responsible for the decline of the Bald Eagle
The pesticide DDT was widely used in the US in the 1940’s - 60’s.
DDT got into the food chain. It affected the eggs - making the
shells thin and weak. Often the eggs cracked before the young
were born.
Additional Threats to Biodiversity
Global Climate Change…
What is it?
How would this
impact species?
Population Growth….
an increase in the number
of individuals in an area
currently 7 billion humans
increasing…. at a rate of
about 222,000 people/day
Over Consumption…
the increasing consumption of natural resources
A prolonged pattern of overconsumption
leads to ENVIRONMENTAL DEGRADATION.
Over Consumption…
the increasing consumption of natural resources
How many cell phones have you owned?
Why did you replace the last one?
Did you NEED a new cell phone?
Over Consumption….
DEVELOPED NATIONS….
• approximately 24 % of the world’s population
• consume about 75% of the world’s resources
• affluent, industrialized nations consume a disproportionate
amount of the Earth’s natural resources
the HIPPO dilemma
(The 5 Main Threats To Biodiversity)
H - habitat loss
I - introduced species
P - population growth
P – pollution
O - over-consumption
ENDEMIC SPECIES – species that are native to and
found only within a limited area
New Guinea
Birds of Paradise
39 species
Area Critical Biodiversity – 1. Tropical Rainforests
• cover less than 7% of the Earth’s land surface
• contain over 50% of the world’s species
Why are species disappearing?
land is cleared for farming, cattle, roads…
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Area Critical Biodiversity – 2. Coral Reefs
• Functions of coral reefs – food, tourism,
protect coasts from waves, source of chemicals
• nearly 60% of coral reefs are threatened by human
activities – overfishing and pollution
Area of Critical Biodiversity – 3. Coastal Ecosystems
• include swamps, marshes, shores and kelp beds
• serve as ….travel routes for many migrating species
and link to land ecosystems
Area of Critical Biodiversity – 4. Islands
Islands often have distinct species –
different from anywhere else
Galapagos Islands – have unique species - marine iguanas, 13
finches, tortoise, flightless cormorant
What is threatening island species? exotics + development
BIODIVERSITY HOTSPOTS –
are the most threatened areas having high species diversity
25 areas have been identified – map on page 268
including Madagascar, New Zealand, Caribbean, Phillppines, …
Madagascar has 33 species of lemur
- lemurs are found nowhere else
Section 3 – The Future of Biodiversity
Captive Breeding - the breeding of species in captivity with the
hope of reintroducing them to their natural habitat
BLACK-FOOTED FERRET
• declared extinct in 1979
• Small population found in 1981
• captive breeding has resulted in reintroduction
into 8 western states
• now over 1,000 mature, wild-born individuals
BLACK FOOTED FERRET
http://www.youtube.com/watch?v=pNLwHlQDdEk
CALIFORNIA CONDOR
• habitat loss, poaching and lead
poisoning brought this species near
extinction
• 1986 – remaining 9 wild Condors
were captured
• began captive breeding program
• 2005 - 121 condors in the wild
Survival of this animal is still in peril.
CALIFORNIA CONDOR
http://www.youtube.com/watch?v=UTi
3ZGGL1J0
GERM PLASM(A) – any form of
genetic material contained
within the reproductive, or
germ cells of an organism
GERM PLASM BANK – stores
germ plasm(a) for future use
and research or speciesrecovery efforts
WHAT CAN BE STORED? –
seeds, sperm, DNA, eggs,
embryos, tissue samples,…
DOOMSDAY
VAULT
• located on the Svalbard Islands, Norway
(within the Arctic Circle)
• the vault aims to safeguard the world’s agriculture
from future catastrophes.
Zoos, Aquariums, Botanical Gardens
Original Idea –
to put exotic animals and plants on display
Why important today • in some cases, these facilities now house the few
remaining members of a species and are perhaps the
species’ last hope for survival –
• living museums of the world’s biodiverisity
Problems with Captive Species – may not reproduce,
small populations are vulnerable to disease and
genetic disorders caused by inbreeding
The most effective way to save species….
is to protect their habitat.
Why is it important to protect entire ecosystems
rather than individual species?
• able to save more species
• species must have a place to live
Endangered Species Act – passed 1973
4 main provisions
1. To compile a list of all endangered and
threatened species in the US
2. To protect from human harm. No part of an
endangered or threatened species can be
hurt, sold or traded.
3. The federal government cannot carry out any
project that jeopardizes threatened or
endangered species.
4. To prepare a species recovery plan
HABITAT CONSERVATION PLAN - attempts to
protect species across large areas of land.
ICUN RED LIST
• published by International Union for the Conservation of
Nature and Natural Resources
• list of species in danger of extinction around the world
Biodiversity Treaty – international
agreement to preserve biodiversity
WWF (World Wildlife Fund) – encourages the
sustainable use of resources and supports
wildlife protection
Conservation International –
helps identify biodiversity hotspots
and
develop ecosystem conservation projects
Greenpeace
International – uses
non-violent
confrontation to raise
the level of awareness
of environmental
threats and raises the
quality of public debate.
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