Sunday, October 12, 2014

The 'Life Form Spectra' of Communities

Ideas

Thought

Reinterpreting verses of the Quran about creation of living organisms in light of the theory of evolution.

Do

Should start reading research papers (refereed to in the book, and on Google Scholar).

Digest

  • Divergence
    • Geographic isolation allows populations to diverge under natural selection.
    • Geographic distributions of species reflects this divergence.
    • All species of lemurs are found only on the island of Madagascar.
  • "Gum trees occur where they do because they evolved there – not because these are the only places where they could survive and prosper."
  • Biomes
    • A map of biomes is not a map of the distribution of species.
    • We recognize different biomes from the types of organisms that live in them.
  • Life forms
    • In 1934, Danish biogeographer Raunkiaer developed the idea of "life forms".
    • "He then used the spectrum of life forms present in different types of vegetation as a means of describing their ecological character."
    • Life forms are defined according to the ways in which buds are protected in different plants.
  • Life forms:
    • phanerophytes: trees exposing their buds high in the air
    • chamaephytes: perennial herbs form cushions in which buds are borne above ground
    • hemicryptophytes: buds are formed at or in the soil surface
    • cryptophytes or geophytes: buds are protected on buried dormant storage organs; These allow the plants to make rapid growth and to flower before they die back to a dormant state.
    • therophytes: "annual plants that depend wholly on dormant seeds to carry their populations through seasons of drought and cold"
  • "Therophytes are the plants of deserts, sand dunes and repeatedly disturbed habitats. They also include the annual weeds of arable lands, gardens and urban wastelands."
  • fauna classification
  • Species present in different geographic locations may belong to the same biome yet be very different taxonomically.
Crocus
Crocus

Questions

  1. How come there are various different species evolving in the same environment?
  2. What's with different species complementing one another in a specific environment?