Chapter 11 Biodiversity: PreservingSpecies

11.1 Biodiversity And The Species Concept

• What is biodiversity? • What are species?– Genetically Similar Organisms Capable of

Interbreeding Among Themselves– With Some Exceptions (Dogs, Wolves and Coyotes)– The Red Wolf (Canis Rufus) – Is it a Species?– Really Problematic at the Microscopic Level

ClassificationLevel Humans Dogs

Kingdom Animalia Animalia

Phylum Chordata Chordata

Class Mammalia Mammalia

Order Primata Carnivora

Family Hominidae Canidae

Genus Homo Canis

Species sapiens familiaris

Below Species Level• Subspecies– Panthera tigris tigris (Bengal Tiger)– Panthera tigris sumatrae (Sumatran Tiger)– Panthera tigris altaica (Siberian Tiger)

• Race: Distinctive Variety of Species or Subspecies– Considered to Have Little Biological Meaning for

Humans• Variety, Strain, Breed, etc.

Molecular Techniques Are Revolutionizing Taxonomy

• “Five Kingdom” System– Animalia– Plantae– Protista (Single-Celled)– Fungi– Bacteria (No Cell Nucleus)

• Levels Above Kingdom– Bacteria are More Different Than Everything Else

Levels Above Kingdom• What’s Bigger than a Kingdom?– Empire? No: Domain or Superkingdom

• Eukarya: Everything With a Cell Nucleus– Every Organism You Can See

• Monera (Bacteria)• Archaea (Many are Extremophiles)• Monera and Archaea outweigh and Outumber Us• We Need Molecular Biology to Detect These

Differences

Molecular Techniques Are Revolutionizing Taxonomy

• The Case of Crocodiles• Ancient Egyptians Knew of Two Kinds of

Crocodiles– Big, Dangerous Deep Water Crocodiles– Smaller, Near-Shore, “Less Dangerous”

• Genetic Studies Show They Were Right• The Less Dangerous Ones Are More Closely

Related to American Crocodiles

How many species are there? • 62,000 Vertebrates (Half are Fish)• A Million Insects (23,000 Fossil)• 250,000 Other Invertebrates• 300,000 Plants (280,000 Broad-Leaf Plants)• Estimated 7-100 Million Unknown• 700 Dinosaurs (9,000 Living Reptiles)• 70,000 Fossil Mollusks

Hot spots have exceptionally highbiodiversity

• New Zealand• Horn of Africa• Southeast Asia-Indonesia• Pacific Islands• Caribbean Islands• Mediterranean• Caucasus• California

11.2 How Do We Benefit From Biodiversity?

• All of our food comes from other organisms• Living organisms provide us with many useful

drugs and medicines • Biodiversity provides ecological services• Biodiversity also brings us many aesthetic and

cultural benefits

11.3 What Threatens Biodiversity?

• Extinction is a natural process • We are accelerating extinction rates • Invasive Species • Island ecosystems are particularly susceptible

to invasive species • What Can You Do? Don’t Buy Endangered

Species Products

11.4 Endangered Species Management

• Hunting and fishing laws have been effective • Legislation is key to biodiversity protection • Recovery plans rebuild populations of endangered

species – Predators Help Restore Biodiversity in Yellowstone

• Private land is vital in endangered species protection • Endangered species protection is controversial • Large-scale, regional planning is needed • International wildlife treaties are important

11.5 Captive Breeding And SpeciesSurvival Plans

• Zoos can help preserve wildlife • We need to save rare species in the wild– “Charismatic’ Species

• Reconstituting Extinct Organisms?– Critics: Focus on Preserving Present