Bio 320- Fundamentals of Ecology
22 January 2013

Global Ecology I: Biomes

Announcements:

• Lab tomorrow - meet in Botany lab for brief intro & equipment pick-up; then carpool across town to Leyden St. trailhead

• Campus SEEDS meeting Wed. 1/23, Bio seminar room (upstairs, E end of hall)

• Thursday - Homework assignment:

  • Learn about negative vs. positive feedbacks in natural systems; use your text, online searches, other sources – make sure you understand the difference, & origin of names (what are alternative, more descriptive names of these 2 processes?)
  • As watch film (on Thurs): take notes, identify the ~12 different systems/examples described, & whether each example involves one of the types of feedback
    take GOOD NOTES so that you can re-visit these examples later!!
  • Turn in @ end of class:
    • 1 (biological/ecological) example of negative feedback & 1 of positive feedback, AT LEAST one of them from the film

    • Describe the feedbacks in diagram form (words, arrows; c.f. a flow chart or concept map)

Review - what does this map show?

Tuesday: Main Goals

• Global Ecology: introduction to Earth's major biomes
• images in Powerpoint on Dr. Dott's O: drive
• define biome
• major plant life forms and their combinations that define biomes
• main climatic factors that constrain & define biomes
• climate diagrams
• distribution of precip., temp., and potential evap. with latitude (Group work & figure in Powerpoint)
• group work:
  • identify a biome type based on its climate diagram

• Evolutionary relationships, & link to physiology & adaptations

Question 1:

In small groups, address these questions for the pairs of photographs below.

1. What phenomenon explains the similarities of these organisms?
2. What ecological constraints could allow or cause such similarities to arise?

Organpipe Cactus - N. America;        Euphorbia - S. Africa

• Examples of convergent evolution: succulents from N. America (cacti) & from Africa (euphorbs)

  • adaptations to similar environmental (climatic) conditions lead to similar growth forms

  • Earth's biomes are similar world-wide because of convergent evolution in similar environments

Question 2: What climatic factors are most important to the distribution of biomes?

(Go to Powerpoint)

Question 3: What Biome is represented  by a given climate diagram?

Example Climate Diagram - what biome?