Announcements Feb 23, 2011 Exam next Wednesday (March 2)
Biodiversity 1 and 2 Lecture Objectives: <ul><li>Be introduced to the diversity of life on Earth </li></ul><ul><li>Understand the mechanisms of diversity loss </li></ul><ul><li>Define and give examples of how nature inspires science </li></ul>
What is biological diversity? “ the variety and variability among living organisms and the ecological complexes in which they occur ” U.S. Office of Technology Assessment (1987)
Scales or types of biological diversity: Genetic diversity - Amount of genetic variation within or among populations of a given species. Species diversity - The number of species in a given community. Community level diversity - Variation in species assemblages based on variation in habitat within an ecosystem type. Ecosystem level diversity - Variation in ecosystems across a landscape or region.
Rarity: A species that is either very uncommon throughout its range, or its range is very small. Endemism: An endemic species occurs no where else. Most common on islands.
Species are groups of interbreeding organisms. Biological Species Concept (E. Mayr) What is a species?
Taxonomy : the study of types of organisms and their relationships. Classification ranked according to - similarity - common ancestry Linnaeus (1707-1778) originator of modern scientific classification of plants and animals
Scientific Classification Kingdom K ing P hillip C an O rder F ried G reen S nails Phylum Class Order Family Genus Species Aves Chordata Animalia Haliaeetus leucocephalus Falconiformes Accipitridae
The Kingdoms of Life Plants Animals Fungi Protists Bacteria Archaebacteria Organisms are classified into groups based on how they make a living
Bacteria Archaebacteria Prokaryotes: do not have membrane bound nucleus nor other organelles, are unicellular. The Kingdoms of Life Organisms are classified into groups based on how they make a living
Plants Animals Fungi Protists Eukaryotes: have membrane bound nucleus and other organelles, can be multicellular or unicellular. The Kingdoms of Life Organisms are classified into groups based on how they make a living
How many species are there? 1.4 -1.7 million described 10-100 million estimated
Animal Diversity 34 Animal Phyla Over 1 million different species of animals have been described < 5 % of described animals have a backbone
From the fossil record we can estimate that bird species last between 1-2 million years (Pimm 1995, Raup 1982). Currently there are about 10,000 species of birds. So, we could expect, under natural conditions for one species to go extinct every 100 years. What do we know from the fossil record?
Hawaii Hawaiian islands are known for endemic fauna. Bird bones from lava tubes can be compared to current birds. The Hawaiian islands were one of the last islands to be colonized by humans. Since human arrival between 1500-2000 years ago, 60 endemic land birds have gone extinct.
Why? Habitat loss coupled with the introduction of avian malaria, rats, and mongoose
New Zealand 44 endemic land birds lost in last 1,000 years
The Dodo A flightless pigeon (about 50 lbs) native only to the island of Mauritius in the Indian Ocean. Around 1505 the Portuguese became the first Europeans to discover the dodo. By 1681 it had been driven to extinction by humans and the feral dogs, pigs, rats, and monkeys introduced by Europeans to Mauritius. The dodo was not the only Mauritian bird driven to extinction in recent centuries. Of the 45 bird species originally found, only 21 still survive.
Last seen: 1914. Passenger Pigeon Reasons: Over-hunting; loss of habitat as forests were cleared and converted to farmland. The passenger pigeon was once the most numerous and successful species of bird to ever exist on earth. Observers reported the sky was darkened by huge flocks that passed overhead. These flights often continued from morning until night and lasted for several days. John Audubon watched a flock fly overhead for three days in 1813, estimating over 2 billion birds. In 1870, even after their numbers had already been considerably diminished, a flock flew over Cincinnati that was a mile wide and 320 miles long, containing over two billion birds. The last passenger pigeon dies in the Cincinnati Zoo in 1914.
Carolina Parakeet With the spread of agriculture, this brilliantly colored bird developed a liking for the seeds of many kinds of fruit and grain crops. For this, and its habit of gathering in great destructive flocks, it was condemned as a pest and subjected to wholesale slaughter. Many were also sold as pets and their feathers were used in hats. Once common in the southeastern United States, the Carolina parakeet became increasingly scarce as deforestation reduced its habitat. Already rare by the mid 1880s, its last stand was in Florida, where, in 1920, a flock of 30 birds was the last ever seen of the only native parrot of the United States. Last seen: 1920
The Great Auk Last seen: 1845 This northern hemisphere flightless bird (equivalent to a penguin), was hunted for food, oil, feathers and eggs. The last breeding population suffered a catastrophe when an island off of Iceland vanished beneath the sea due to a volcanic eruption. The last remaining individuals from other locations winked out by 1845. The last Great Auk recorded on St. Kilda Island was captured alive and was kept tied up for three days before being beaten to death, suspected of being a witch.
California Condor Next? North America ’ s largest bird (only Andean Condor is larger for flying species). Last individuals brought into captivity in 1985. Captive breeding has been somewhat successful and re-introductions into California ’ s lost coast and the Grand Canyon have been attempted the last few years.
Summary: Estimates from the fossil record suggest that one species may go extinct every 100 years. If we sum up all birds that have gone extinct in the Pacific over the last 30,000 years since human colonization, we estimate a loss of 2,000 species. This is one species every 15 years or ten times the background extinction rate. Since 1600 A.D., 116 bird species have gone extinct. That is one extinction every 3-4 years or almost 100 times background. There are another 1,029 birds listed as threatened worldwide. (and we only talked about birds - they may be less sensitive than other groups like mammals…)
Do all species matter? Is there redundancy in communities? On average, there are only 2 degrees of separation between any two species in a food web. Paul Ehrlich made an analogy between species in communities and rivets on the wing of an airplane. Removing a few rivets from an airplane is undoubtedly safe. How many are you willing to remove?
Many species are in danger of extinction WHY?? If current trends continue, 1/5 of all current plant and animal species could be gone or on the road to extinction by 2050.
Percentage of threatened or endangered species in the U.S. imperiled by: Why are species declining? Disease - 3% Overexploitation - 17% Pollution - 24% Invasive species - 49% Habitat degradation and loss - 85% Dave Wilcove et al. 1998 BioScience
Why value diversity? Motivation can be based on many principles. Ethical Moral Aesthetic Monetary Spiritual Environmental Anthropocentric
Disappearing bees threaten ice cream sellers By Parija B. Kavilanz, CNNMoney.com February 17 2008 NEW YORK (CNNMoney.com) -- Haagen-Dazs is warning that a creature as small as a honeybee could become a big problem for the premium ice cream maker's business. At issue is the disappearing bee colonies in the United States, a situation that continue to mystify scientists and frighten foodmakers. That's because, according to Haagen-Dazs, one-third of the U.S. food supply - including a variety of fruits, vegetables and even nuts - depends on pollination from bees. Haagen-Dazs, which is owned by Nestle, said bees are actually responsible for 40% of its 60 flavors - such as strawberry, toasted pecan and banana split.
“ Approximately half of the prescribed medications in the U.S. and half of the new drugs approved by the FDA in the past 25 years derive directly or indirectly from nature. ” Bernstein and Ludwig, The Importance of Biodiversity to Medicine. 1) Nature provides compounds of immense importance to science and medicine “ Natural Products ”
“ Bio-inspiration ” 2) Nature provides inspiration for a wide variety of scientific disciplines
Science Daily Aug. 28, 2002 Scientists Prove How Geckos Stick, Unlock Secrets To Making Artificial Gecko Glue Geckos, nature's supreme climbers, can race up a polished glass wall at a meter per second and support their entire body weight from a wall with only a single toe. But the gecko's remarkable climbing ability has remained a mystery since Artistotle first observed it in fourth century B.C. Now a team of biologists and engineers has cracked the molecular secrets of the gecko's unsurpassed sticking power--opening the door for engineers to fabricate prototypes of synthetic gecko adhesive. First velcro….
Science Daily Aug. 23, 2006 Engineers Create Gecko- inspired, High-friction Micro-fibers Inspired by the remarkable hairs that allow geckos to hang single-toed from sheer walls and scamper along ceilings, a team of researchers led by engineers at the University of California, Berkeley, has created an array of synthetic micro-fibers that uses very high friction to support loads on smooth surfaces. Quarter clinging to a steeply inclined glass slide. The glass slide is inclined 80 degrees from horizontal. The contacting side of the quarter is covered by a sheet of the micro-fiber array. No adhesive is used to keep quarter from sliding. First velcro….
Aug 21, 2006 Trap-jaw ant has world's fastest bite The mandibles of the trap-jaw ant close at speeds up to 145 mph, the fastest predatory strike in the animal kingdom. Scientists have discovered the fastest bite in the world, one so explosive it can be used to send the ant that performs it flying through the air to escape predators. These powerful jaws could serve as inspirations for the propulsion systems of miniature robots, says researcher Andrew Suarez , an ecologist and entomologist at the University of Illinois at Urbana-Champaign .
8 October 2008 The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Chemistry for 2008 jointly to Osamu Shimomura, Marine Biological Laboratory (MBL), Woods Hole, and Boston University Medical School, MA, USA, Martin Chalfie, Columbia University, New York, NY, USA Roger Y. Tsien, Howard Hughes Medical Institute, University of California, San Diego, La Jolla, CA, USA "for the discovery and development of the green fluorescent protein, GFP".
Invisibility cloak closer than ever to reality Jan. 15, 2009 Unlike Harry Potter's, the real deal will likely be cheap, easily reproducible Researchers have created an invisibility cloak of sorts, though it looks more like a yellow bathmat than Harry Potter's famous cloth. The cloak is shown lying over a bump on a flat surface. Both the bump and surface are covered in a reflective coating. The cloak makes it appear that microwaves hitting the bump are actually reflecting off a flat surface. "I think that within six months it's certainly viable [a cloak for visible light]," said David Smith, a professor at Duke University and author of the Science paper.
Points to Know <ul><li>Be familiar with the system for classifying living things. Know the biological species concept. </li></ul><ul><li>Be able to define biological diversity and scales of diversity. </li></ul><ul><li>Know the relative diversity of different animal phyla </li></ul><ul><li>Understand historical versus current extinction rates. </li></ul><ul><li>Understand 2 principle ways that nature can advance science </li></ul>