Biodiversity and Conservation

Levels of Biodiversity Humans are reducing Earth’s diversity of

life Biodiversity – sum total of all organisms

in an area Split into three specific levels:

Species diversity Genetic diversity Ecosystem diversity

Species Diversity Species Diversity = the number or

variety of species in the world or in a particular region Richness = the number of species Evenness or relative abundance =

extent to which numbers of individuals of different species are equal or skewed

Speciation generates new species and adds to species richness

Extinction reduces species richness

Taxonomy

Taxonomists = scientists who classify species

Physical appearance and genetics determines a speciesGenera = related species are grouped togetherFamilies = groups of genera

Every species has a two-part scientific name: genus and species

Subspecies Subspecies =

populations of species that occur in different areas and differ slightly from each other Divergence stops

short of separating the species

Subspecies are denoted with a third part of the scientific name

Siberian tiger = Panthera tigris altaica

Bengal tiger = Panthera tigris tigris

Genetic Diversity Encompasses the differences in DNA among

individuals within species and populations The raw material for adaptation to local

conditions Populations with higher genetic diversity can

survive They can cope with environmental change

Populations with low genetic diversity are vulnerable To environmental change Disease Inbreeding depression = genetically similar

parents mate and produce inferior offspring

Diversity Ecosystem diversity = the number

and variety of ecosystems Also encompasses differing

communities and habitats Rapid vegetation change and varying

landscapes within an ecosystem promote higher levels of biodiversity

Diversity Species are not evenly distributed among

taxonomic groups Insects predominate over all other life-forms 40% of all insects are beetles

Groups accumulate species by Adaptive radiation Allopatric speciation (species isolation) Low rates of extinction

Review Evolution Microevolution, macroevolution, natural selection,

artificial selection, fitness, adaptation, niche, mutation, sympatric vs. allopatric speciation, bottleneck, founder effects.

Measuring Biodiversity Out of the estimated 3 - 100 million species

on Earth, only 1.7 - 2 million species have been successfully catalogued

Very difficult to identify species Many remote spots on Earth remain

unexplored Small organisms are easily overlooked Many species look identical until thoroughly

examined Entomologist Terry Erwin found 163 beetle

species specialized on one tree species Refer to lab and Simpson’s Index

Biodiversity is not evenly distributed

Living things are distributed unevenly across Earth

Latitudinal gradient = species richness increases towards the equator

Canada has 30 - 100 species of breeding birds, while Costa Rica has more than 600 species

Latitude Gradient and Biodiversity

Loss of Species

Extinction = occurs when the last member of a species dies and the species ceases to exist

Extirpation = the disappearance of a particular population from a given area, but not the entire species globally Can lead to extinction

Extinction is a natural process

Paleontologists estimate 99% of all species that ever lived are now extinct

Background rate of extinction = natural extinctions for a variety of reasons 1 extinction per 1 to 10

million species for mammals and marine species

1 species out of 1,000 mammal and marine species would go extinct every 1,000 to 10,000 years

Endangered and Threatened Species

Endangered and Extinct Species

Could become extinct soon. Population declining very

fast.Spectacled Bear

ThreatenedEndangered

Endangered and Extinct Species

Characteristics of Endangered Species• Extremely small range• Requiring large territories• Living on islands• Low reproductive success• Specialized breeding areas• Specialized feeding habits

Tiburon mariposa lilyCalifornia condor

Hawaii ‘O’ oBlue whaleGreen sea turtle

Giant panda

Endangered and Extinct Species- Most Impacted areas- Hawaii and other island habitats- Tropical rain forests http://www.pbs.org/wnet/nature/episodes/the-

dragon-chronicles/video-komodo-dragon-chases-rom/4520/

Past Mass Extinctions In the past 440

million years, mass extinctions have eliminated at least 50% of all species

After every mass extinction the biodiversity returned to or exceeded its original state

Current Mass Extinction is Human Caused

During this Quaternary period, we may lose more than half of all species Hundreds of human-induced species

extinctions, and multitudes of others, teeter on the brink of extinction

The current global extinction rate is 100 to 1,000 times greater than the background rate This rate will increase tenfold in future

decades due to human population growth and resource consumption

Loss of Biodiversity is more than extinction

Decreasing numbers are accompanied by smaller species’ geographic ranges

Genetic, ecosystem, and species diversity are being lost.

The Living Planet Index summarizes trends in populations Between 1970 and 2003,

the Index fell by 30%

Causes of Biodiversity Loss Reasons for biodiversity losses are

multifaceted, complex, and hard to determine Factors may interact synergistically

Four primary causes of population decline are: Habitat alteration Invasive species Pollution Overharvesting

Global climate change now is the fifth cause

Habitat Loss The greatest cause of

biodiversity loss Farming simplifies

communities Grazing modifies the

grassland structure and species composition

Clearing forests removes resources organisms need

Hydroelectric dams turn rivers into reservoirs upstream

Urbanization and suburban sprawl reduce natural communities

A few species (i.e., pigeons, rats) benefit from changing habitats

Invasive Species Introduction of non-native species to new

environments Accidental: zebra mussels Deliberate: food crops

Island species are especially vulnerable Invaders have no natural predators,

competitors, or parasites Cost billions of dollars in economic

damage

Pollution Harms organisms in many ways

Air pollution degrades forest ecosystems Water pollution adversely affects fish and

amphibians Agricultural runoff harms terrestrial and aquatic

species The effects of oil and chemical spills on wildlife

are dramatic and well known The damage to wildlife and ecosystems

caused by pollution can be severe But it tends to be less than the damage caused

by habitat alteration or invasive species

Overharvesting Vulnerable species are large, few in

number, long-lived, and have few young (K-selected species) The Siberian tiger is hunted without

rules and regulations The early 1990s saw increased

poaching because of powerful economic incentives

Many other species affected: Atlantic gray whale, sharks, gorillas

Today the oceans contain only 10% of the large animals they once did

Climate Change Emissions of

greenhouse gases warms temperatures Modifies global weather

patterns and increases the frequency of extreme weather events

Increases stress on populations and forces organisms to shift their geographic ranges

Most animals and plants will not be able to cope

Biodiversity is good for ecosystems (ecosystem services) Provides food, shelter, fuel Purifies air and water, and detoxifies wastes Stabilizes climate, moderates floods, droughts,

wind, temperature Generates and renews soil fertility and cycles

nutrients Pollinates plants and controls pests and disease Maintains genetic resources Provides cultural and aesthetic benefits Allows us to adapt to change

Biodiversity Loss in an Ecosystem Biodiversity increases the stability and resilience

of communities and ecosystems Decreased biodiversity reduces a natural

systems ability to function and provide services to our society

The loss of a species affects ecosystems differently If the species can be functionally replaced by

others, it may make little difference Extinction of a keystone species may cause

other species to decline or disappear “To keep every cog and wheel is the first

precaution of intelligent tinkering” (Aldo Leopold)

Biodiversity affects food security Genetic diversity within crops is

enormously valuable Turkey’s wheat crops received $50 billion

worth of disease resistance from wild wheat

Wild strains provide disease resistance and have the ability to grow back year after year without being replanted

Biodiversity and Medicines Each year

pharmaceutical products owing their origin to wild species generate up to $150 billion in sales The rosy periwinkle

produces compounds that treat Hodgkin's disease and leukemia

Some economic benefits of biodiversity People like to experience

protected natural areas, creating economic opportunities for residents, particularly in developing countries Costa Rica: rainforests (Excellent

at ecotourism) Australia: Great Barrier Reef Belize: reefs, caves, and

rainforests A powerful incentive to preserve

natural areas and reduce impacts on the landscape and on native species

But, too many visitors to natural areas can degrade the outdoor experience and disturb wildlife

People Value and seek nature Biophilia = connections that humans

subconsciously seek with life Our affinity for parks and wildlife Keeping of pets High value of real estate with views of

natural lands Nature deficit disorder = alienation from

the natural environment May be behind the emotional and physical

problems of the young

Conservation Biology Conservation biology = devoted to

understanding the factors that influence the loss, protection, and restoration of biodiversity Arose as scientists became alarmed at the

degradation of natural systems An applied and goal-oriented science

Conservation Biology Conservation biologists integrate evolution and

extinction with ecology and environmental systems Design, test, and implement ways to mitigate human

impacts Conservation geneticists = study genetic

attributes of organisms to infer the status of their population

Minimum viable population = how small a population can become before it runs into problems

Metapopulations = a network of subpopulations Small populations are most vulnerable to extinction

and need special attention

Should we focus on endangered species? Endangered Species Act (1973) (ESA) =

forbids the government and private citizens from taking actions that destroy endangered species or their habitats-40 Year anniversary! To prevent extinction Stabilize declining populations Enable populations to recover

US has approximately 2050 endangered species.

http://www.fws.gov/endangered/ http://www.nmfs.noaa.gov/pr/laws/esa/

ESA Through federal action and by encouraging the establishment of

state programs, the 1973 Endangered Species Act provided for the conservation of ecosystems upon which threatened and endangered species of fish, wildlife, and plants depend. The Act: authorizes the determination and listing of species as endangered and

threatened; prohibits unauthorized taking, possession, sale, and transport of

endangered species; provides authority to acquire land for the conservation of listed species,

using land and water conservation funds; authorizes establishment of cooperative agreements and grants-in-aid

to States that establish and maintain active and adequate programs for endangered and threatened wildlife and plants;

authorizes the assessment of civil and criminal penalties for violating the Act or regulations; and

authorizes the payment of rewards to anyone furnishing information leading to arrest and conviction for any violation of the Act or any regulation issued thereunder.

Amendments to ESA

Habitat Conservation Plans• 1982 amendment to ESA• Landowner allowed to set aside land

for endangered species, but develop other land with those species

Successes Peregrine falcons, brown pelicans, bald eagles,

and others have recovered and are no longer listed

Intensive management has stabilized other species The red-cockaded woodpecker 40% of declining populations are now stable

These successes occur despite underfunding of the U.S. Fish and Wildlife Service and the National Marine Fisheries Service In recent years, political forces have attempted to

weaken the ESA http://www.pbs.org/wnet/nature/episodes/amer

ican-eagle/video-full-episode/4349/

Ways to preserve biodiversity

Captive breeding – individuals are bred and raised with the intent of reintroducing them into the wild Zoos and botanical gardens

Some reintroductions are controversial Ranchers opposed the reintroduction of

wolves to Yellowstone National Park Some habitat is so fragmented, a

species cannot survive Seed Banks

Cloning???? Cloning – a technique to create more

individuals and save species from extinction Most biologists agree that these efforts

are not adequate to recreate the lost biodiversity

Ample habitat and protection in the wild are needed to save species

Jurassic Park

Strategies Conservation biologists use particular species

as tools to conserve communities and ecosystems Protecting the habitat of these umbrella species

helps protect less-charismatic animals that would not have generated public interest

Flagship species – large and charismatic species used as spearheads for biodiversity conservation The World Wildlife Fund’s panda bear

Some organizations are moving beyond the single species approach to focus on whole landscapes

International Conservation UN Convention on International Trade

in Endangered Species of Wild Fauna and Flora (1973) (CITES) – protects endangered species by banning international transport of their body parts

Convention on Biological Diversity (1992) – Seeks to conserve biodiversity Use biodiversity in a sustainable manner Ensure the fair distribution of biodiversity’s

benefits By 2007, 188 nations had signed on Iraq, Somalia, the Vatican, and the U.S. did

not join

Hot spots Biodiversity hotspots – prioritizes

regions most important globally for biodiversity Support a great number of endemic

species = species found nowhere else in the world

The area must have at least 1.500 endemic plant species (0.5% of the world total)

It must have lost 70% of its habitat due to human impact

2.3% of the planet’s land surface contains 50% of the world’s plant species and 42% of all terrestrial vertebrate species

Community Based Conservation Protecting habitats makes good sense, but

this affects people living in and near these areas

Community-based conservation = conservation biologists actively engage local people in protecting land and wildlife Protecting land deprives people access to

resources But, it can guarantee that these resources will

not be used up or sold to foreign corporations and can instead be sustainably managed

Many projects have succeeded But, others have not, due mainly to funding

problems

Economic Incentives Debt-for-nature swap = a conservation

organization pays off a portion of a developing country’s international debt In exchange for a promise by the country to

set aside reserves Fund environmental education, and Better manage protected areas

Conservation concession = conservation organizations pay nations to conserve, and not sell, resources

Costa Rica and Debt Swap Under the U.S. Tropical Forest Conservation

Act, the United States agreed to forgive $26 million of Costa Rica’s debt in return for the Central American nation’s commitment to redirect that money toward conservation inside its borders. The U.S. government appropriated $12.6 million for the effort. Both Conservation International (CI) and The Nature Conservancy each gave $1.26 million to the debt purchase at a discounted rate.

Wildlife management Differs from conservation biology in that wildlife

managers focus more often on common organisms and manage those species primarily for human benefits

Management of Aquatic Organisms• Freshwater fisheries primarily managed

by state fishing regulations• Ocean fisheries commonly viewed as common

property-this has lead many species close to commercial extinction

Case Studies and FYI Sharks-32% of the world’s open-ocean species are

threatened. They are keystone species and can potential help cancer research.

E. O. Wilson-Champion of Biodiversity Vanishing Amphibians-an indicator Species.

Go to the media centers website and log onto discovery education-search Vanishing Frogs for a documentary

Polar Bears and Climate Change Elephants in Africa Black Rhinos and Poaching Kudzu, zebra mussels, termites, gypsy moths, Cane

toads http://www.youtube.com/watch?v=4mvV8OT-mmE (don’t know if you can get this at school)

Birds of Thailand