BIO141 FINAL

• Conservation Biology


  The integrated study of ecology, evolutionary biology, physiology, molecular biology, and genetics to sustain biological diversity at all levels
• Levels of Biodiversity


  • Genetic diversity
  • Species diversity
  • Ecosystem diversity
• Reasons to care about biodiversity


  • Human sense of connection to nature and all forms of life termed biophilia
  • Other species are entitled to life is a pervasive theme of many religion and the basis of a moral argument to protect biodiversity
• Main causes of losing biodiversity


  • Habitat loss
  • Introduced species- species moved by humans, either intentionally or accidentally, from its native location to a new geographic region
  • Overharvesting
  • Global change
• How is Earth changing due to human actions


  • Nutrient enrichment
  • Toxin accumulation
  • Climate change
  • Ozone depletion
• What can you do?


  • End the overharvesting of species in decline
  • Protect "hot spots" of high biodiversity
  • Establish regional networks of protected areas
  • Combat climate change and other global environmental change
  • Restore or preserve habitat of threatened species
• Invertebrate chordates


  • Lancelets
  • Tunicates
• Vertebrate chordates


  • Vertebrates
  • Backbone
  • More HOX genes (innovations)
  • Neural crest cells
• Major innovations in the evolutionary history of vertebrates


  • Head (cranium or skull)
  • Vertebrates
  • Jaw/fin/lung
  • Limbs
  • Amniotic egg
  • Milk/hair
• Why fish are successful in water


  • Vertebrates with jaws increase feeding efficiency
  • Evolution of jaws through descent with modifications
• Challenges for animals to live on land

  • Oxygen (gills to lung)
  • Water
  • Mobility (limbs)
  • Reproduction (most important innovation)
• Amniotes


  Tetrapods that have terrestrially adapted egg with amnion, chorion, the yolk sac, and the allantois
• Rib cage to ventilate lungs
• Evidence used to understand how vertebrates moved from water to land


  • Fossil evidence-dinosaurs
• Modes of reproduction in vertebrates


  • Oviparous - external fertilization, hatch outside, yolk for nutrient
  • Viviparous - internal fertilization, placenta nutrient, give birth
  • Ovoviparous - internal fertilization, yolk for nutrient
• Hagfish


  • Head- active predation
  • Feed on worms/dead fish
  • All marine
  • Smelly well
  • Produce slime to escape (Biomimicry)
• Lampreys


  • Marine and freshwater
  • Larvae
  • Adults
  • Have vertebrate
• Fishes


  • Chondrichthyes - Sharks, rays, endoskeleton-mainly cartilage, feeding
  • Osteichthyes - Bony fishes, mineralized skeleton, fins, operculum, scales, lateral line
  • Lobe-finned fish - Coelacanths, Lungfish
• Amphibians


  • First modern tetrapods
  • Two lives (water to land)
  • Reproduce in water - external fertilization, oviparous, aquatic larva, metamorphosis
  • Axolotl - regeneration, paedomorphosis
• Reptiles


  • First vertebrate with amniotic eggs
  • Internal fertilization
  • Most oviparous
  • Some viviparous (some lizards)
  • Most ectothermic
• Birds


  • Endothermic
  • Benefits of flying - avoid predators, explore new habitats
  • Costs of flying - energy
  • Adaptations - wing and feather, bone structure/organ reduction, size of heart
  • Flightless birds - secondary adaptations on islands and in water
• Mammals


  • Mammary glands- milk
  • Hair and skin fat - endothermic
  • Kidney - water and waste balance
  • Larger brain
  • Differentiated teeth
• Monotremes


  • Only egg (amniotic egg) laying mammals
  • Oviparous
  • Reptile-like egg (internal fertilization)
  • Nurse young with milk - Platypus, Echidna
• Marsupials


  • Marsupium-nursing pouch
  • Opossum, kangaroos
  • Give birth (viviparous), newborn's journey to the pouch
• Eutherians (placental mammals)


  • Give birth
  • Prolonged gestation
  • Placenta
• Primates


  • Grasping hands, feet
  • Big brains
  • Shorter jaws
  • Digits with flat nails
  • Binocular vision - forward-facing eyes
  • Parental care
• Humans


  • Large brain
  • Bipedality (walking upright)
  • Tool use
• Evidence of human evolution


  • Hominins – group consisting of humans and the extinct species that are more closely related to us than to chimpanzees
• Hypotheses on human skin color


  • Folate-vitamin D hypothesis - Folate needed for DNA replication, cell division, sperm; UV destroys folate, low level causes birth defects; Vitamin D required for healthy bone, requires UV
• Hypothesis


  A proposed explanation, based on past reasoning
• Theory


  Repeatedly tested and supported, reliable
• Inductive reasoning


  Logical thinking to form conclusions based on observations, discovery of science (Darwin's work, Jane Goodall)
• Deductive reasoning


  Hypothesis based science, experimentation, conclusions based on research results, make predictions
• Biology


  The study of life
• Science


  Pursuit of knowledge using the scientific method
• Strength and limitations of science


  • Strength - way to discover and learn
  • Limits - uncertainty, time, dynamic, things that cannot be studied (does God exist?)
• Characteristics of life


  • Order
  • Regulation
  • Reproduction
  • Growth and development
  • Response to the environment
  • Evolutionary adaption
  • Energy processing
• Themes and organization in Biology


  • Organization
  • Information
  • Energy and matter
  • Interactions
  • Evolution
• Biological evolution is a pattern of change revealed by data from many scientific disciplines, and the process of the mechanisms that cause the observed pattern of change
• Thinkers and ideas that influenced the Darwinian view of life


  • Aristotle - viewed species as fixed (unchanging)
  • Hutton - gradualism or cumulative effect
  • Cuvier - sedimentary strata with fossils
  • Lyell - geological events are same and in the past
  • Lamarck - organisms respond to changes (correct), inheritance of acquired characteristics (incorrect)
  • Darwin - flora and fauna (plants and animals), fossils, Galapagos islands