chapter 10 biodiversity. what is biodiversity? bio = diversity = variety biodiversity is short...
TRANSCRIPT
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)…
• 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
• 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
Indian Spectacled Monkey
Bromeliad
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 panthers2011 – 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
• 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/panthera-pardus-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 breedingCHEETAH - 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/MaizeTomatoBeansPeanutPotato
Sweet potatoAvocadoPumpkinPineapple
CocoaVanilla
Peppers
Wheat Sesame
ChickpeasFigs
LentilCarrot
PeaOkraDate
WalnutCoffeeCowGoatPig
Sheep
SoybeansRice
BananaCoconutLemonLime
OrangeCucumberEggplant
TurnipTea
BlackPepper Chicken
Hybrids
• most new crop varieties are hybrids…. developed by combining genetic material from more than one population
• 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,
andwas 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 Woodpeckerextinct 1960’s
Other factors that put species at risk….• 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?
• habitat destruction…• habitat fragmentation….• habitat degradation….• invasive/exotic species….• harvesting, hunting and poaching….• pollution….
What are the causes of species loss (extinction)…
• 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?
• 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 lossI - introduced speciesP - population growthP – pollution O - over-consumption
ENDEMIC SPECIES – species that are native to and found only within a limited area
New GuineaBirds 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…
…
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=UTi3ZGGL1J0
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 species-recovery 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 agriculturefrom 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 19734 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.