Biodiversity

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Biodiversity
How many species do we have? Rates of
Extinction Why Care? Causes Cost of
Invasives Solutions
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Ecological Diversity and Redundancy

• Aircraft Rivet Story

How many rivets do you think there are in a
Boeing 747? There are probably thousands but
each single rivet is as important as the
thousands in terms of maintaining the structural
integrity of the entire airplane. Now imagine
the following series of events take place on your
next trip. You have just boarded the plane and
are comfortably settled into your seat. You look
out the window and see a person o the wing. This
person is taking one of the rivets out of the
wing! You are (or should be) alarmed and call
the stewardess. You complain that it is not a
good thing for the person to be taking a rivet
out of the wing of the plane. The stewardess
calms your feats by telling you that you should
not worry because there are thousands of rivets
in the wing of this plane. She further tells you
that the person extracting the rivets is getting
5.00 per rivet and will be extracting one rivet
from the other wing also. Well, you take off and
arrive safely at your destination. On your
return flight, the same thing happens but now the
person is extracting two rivets form each wing.
The stewardess tells you that again it is alright
because the person is now getting 10.00 per
rivet. Well this storey could go on and on but
lets get to the point. How many rivets,
regardless of the economic value, would you allow
to be taken out of the plane before you fear for
its structural integrity?
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Ten Reasons to Care About Biodiversityby David
Braun

•  
• Every day the impact of humans on the
  environment increases. From a myriad of human
  activities comes a dizzying reduction in the
  number of plants and animals the earth can
  support. Scientists refer to this, with alarm,
  as the loss of biological diversity. Where there
  were once hundreds or thousands of species, only
  dozens may remain.
• Texas stands to lose more than almost any other
  state. Within its borders are at least eleven
  distinct ecological regions, each with its own
  special plants and animals.
• If you are thinking, So what? Why should I care
  about the loss of some obscure fish or bird?
  read on. Here are ten reasons to care about
  preserving biological diversity.
•  
• Because its there or The Moral Argument We
  did not create life on earth and it is not our
  place to destroy it. We share this planet with
  millions of other species, and it violates all
  our civilized notions of respect and fairness to
  shove another species out of existence.
• Dont pop rivets on the spaceship or The
  Practical Argument Nature and all its creatures
  are one complex, interrelated machine. Killing
  species is like randomly popping out rivets on
  the spaceship earth one or two may not be
  noticed, but at some point the whole things will
  come apart. to survive we need the whole
  ecosystem.
• Theres gold in them thar hills or The Economic
  Argument We have not even begun to discover the
  economic potential of other species. A few dozen
  plants and animals provide the bulk of our food,
  clothing, and building materials. Many, many
  species are being lost before anyone has given
  any thought to their economic potential.
• Isnt Nature beautiful? or The Aesthetic
  Argument Nature is beautiful and interesting.
  Our lives are enriched by its beauty. Our
  artists and writers are inspired by it. Our
  hearts are uplifted by the grandness of wild
  places. We all lose when such beauty is lost.
• Incest is for idiots or The Genetic Strength
  Argument In genetic diversity is the strength
  to adapt and survive. All plant and animal
  breeders know that a key to improving
  domesticated species is to replenish them with
  genes from wild stocks. With the loss of
  species, we impoverish the future gene pool for
  agriculture and other natural resource-based
  industries.
• Oh no! Bread mold in my petri dish or The
  Research Argument Everyone knows that
  penicillin was derived from bread mold. But did
  you know that more than half of all modern
  medicines can be traced to wild organisms?
  Thousands of species are being thoughtlessly
  destroyed before they can be thoroughly
  researched.
• Inquiring minds want to know or The Education
  Argument Nature is fascinating. Behaviors and
  adaptations of plants and animals can be a
  mind-expanding as they are interesting. In each
  generation, discovering the marvels of Nature can
  be the spark that ignites a lifelong quest for
  knowledge.
• Its better than television or The Recreation
  Argument Outdoor recreation provides a
  connection to nature that most of us feel is
  essential. Biodiversity supports numerous
  outdoor activities from hunting and fishing to
  birdwatching and spelunking. In fact, outfitting
  for camping, canoeing, hiking and related nature
  study has emerged as one of our fastest growing
  industries.
• Consider the lilies of the fields or The
  Philosophy Argument Humans have always asked
  the universal questions, Who are we? Why are we
  here? An appreciation of nature may not give the
  final answers but it shapes our understanding
  that we are only a part of a much larger
  creation.
• Were there really elephants, Mommy or The
  Legacy Argument Can you truly say you dont
  care that the world we leave our children wont
  have wild elephants. or rhinoceroses? Or a
  million other species that were here when we
  came? Or vast prairies? Or rainforests? Or
  wilderness of any kind? If you can say you dont
  care, then lets hope the future children of the
  world dont care either. They wont have a
  choice.

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Numbers of Species
How many species do we have? Earth 4.7 billion
years old First Life 3.7 billion years ago
(bacteria) 500 million total species have
existed 5-30 million species now exist Most
have gone extinct, so whats the worry???? Who
can make a species??? Why dont we know? Many
organisms - we have found the big ones. Anyone
have a pet slime mold?
Named organisms - only 1-7 of all
species!!!
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Extinction Rates
Natural rates of Extinction Episodic Mexican
Meteor 65 my ago (so-long, dinos) Vertebrates
Historical 1 every 1000 years
(Low) Current 1 every 9 months Losing
species faster than we can find them 1,000
20,000 species per year recall 3.5 billion
yrs of evolution
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Biodiversity and Food
Why do we care Food Plants to Food Crops
Genetic Resources 250,000 known
species 80,000 have food value lt3,000 tried
for cultivation 150 commercially
cultivate 30 major world food crops
7 species largely feed the world (gt100
million MT food/yr)
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Genetic Resources and Food
Original Source of food e.g. corn
teosinte - Mexico believed to be ancestor of
corn found on only 6 ha (15 acres) of
land! 135,000 reserve to protect source
Teosinte, above, started out as a single stalk of
kernels, each enclosed in its own individual
husk. Over time, artificial selection produced
higher yielding strains with more tender kernels
and husks until we can recognize the first corn
cobs (Center). Today's modern corn (Right) is a
giant mutant version so freakishly large it could
not grow in the wild and would not be able to
reproduce without human help.
brentrasmussen.com/log/node/155
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Genetic Resources and Individual Diversity
What do these vegetables have in
common?Brassica
Wild Brassica oleracea
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Biodiversity Medicine
Medicine Cancer drugs e.g. Taxol - Taxus
In 1989, a famous study at John Hopkins
University showed that yew was able to help women
with "incurable" ovarian cancer. Taxol was
discovered in the 1960s in the bark of the
Pacific yew tree. But scientists soon realized
they had a problem It takes one yew tree about
200 years to produce the bark needed for one dose
of the cancer-killing miracle. They did not
realize at the time that the needles are also
safe and effective.During the 1980s, as Taxol
showed great promise in human tests of ovarian
and breast cancer, researchers around the world
competed to create a synthetic version of the
drug. Bob Holton won the race in 1989 at FSU. By
1994, Taxol was selling in 50 countries around
the world. By 2000, the sales were over 1.5
billion dollars.
Taxus brevifolia
Pacific yew grows along the Pacific Coast of
southeastern Alaska southward through western
British Columbia to central California
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Other Medical Uses
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Biodiversity Ecosystem Control
Studies linking diversity and stability at Cedar
Creek Long-Term Ecological Research Site
Increased plant diversity better drought
resistance better resistance to invasive
species

• The stability and resilience of grassland
  ecosystem productivity in response to a major
  drought were highly dependent on plant
  biodiversity.
• Productivity in least diverse plots fell to
  less than 1/8 of its pre-drought average, whereas
  that in the most diverse plots fell to only 1/2
  of its pre-drought average.
• By the 4th year after drought, productivity in
  the most diverse plots had recovered, but low
  diversity plots still had significantly less
  biomass than before the drought.
• Biodiversity increased drought resistance and
  resilience because more diverse plots were more
  likely to contain drought-resistant species that
  grew and compensated for the loss of
  drought-sensitive species.

Higher local plant diversity led to lower rates
of invasion by exotic, non-native plant species.
Higher plant diversity leads to lower levels of
limiting resources, and lower resource levels
caused reduced invasion rates.
Cedar Creek Long-Term Ecological Research Site
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Biodiversity Predator-Prey Balance
Ecosystem Control Cougars, Deer, and
Forests Recall food web Remove
cougars What happens to deer population? What
happens to tree seedlings? What happens to forest
value and services?
users.eoni.com/eaglecap/pats_suudio.htm
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Reintroduce Cougars?
Benefits Restore Ecological Balance Protect
Forests Challenges Public Resistance Safety
Fear Hunters
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Extinction Causes
Percent of Total Habitat
Loss 30 Commercial Hunting 21 Intro.
Species 16 Pest control 7 Hunting for
food 6 Pet trade 5 Pollution 3
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Characteristics of Species Facing Extinction
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Biodiversity Hotspots
http//www.biodiversityhotspots.org/xp/Hotspots
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Invasive Species
Cost of Invasive Species Dave
Pimental,Corenell 137 billion/yr 500/per
son/y Reasons for introductions Aesthetics
starlings Loss of native species Recreation Brow
n Trout push out native rainbows Pheasants
native to where?? Economics Gypsy moth Forest
Damages Accidental Zebra Mussel Lake Erie,
now in French Creek threat to native mussel
species
Gypsy Moth larva
Sandy Lake PA Mussel infested with zebra mussels
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Damage by Invasive Species
Damage crops Rabbits in Australia Contaminate
food Norway rats Power outages brown tree
snakes Clog water pipes zebra mussel Lower
water tables eucalyptus Block navigation hydrilla
Reduce water O2 water hyacinth Reduce
pollination bee mites Damage structure Formosan
termites Enhance wildfires eucalyptus (CA) ,
Brazilian pepper tree (FL) Promote
erosion miconia (Philippines) Decimate
fisheries green crabs Destroy timber gypsy
moths Toxic reactions giant hogweed Cause
disease mosquitos, West Nile
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Species Approach
Endangered Species Act Reintroductions
Success of Yellowstone wolves Management
Prevent new invasives where possible
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Species Approach v. Ecosystem Approach