Biodiversity

Tuesday, March 13, 2007

A simple comparison between a Madagascan and a typical Cape Flats species (within the context of the Gondwanan split)

The Restionaceae family enjoys wide distribution in South Africa and is more restricted on the larger African continent. The current distribution appears to have underlying gondwanan origins (Linder et al, 2003). Linder et al (2003) further suggests that west Gondwana (Africa, South America) separated from east Gondwana (Australia, Antarctica, Madagascar, India) approximately 180-150 million years ago in the Jurassic. Therefore the restio species of Madagascar have been (to a large extent) evolving separately from those extant on the African mainland for more than 150 million years. Below are some differences between a South African Cape floristic species (Thamnocortus spicigerus) and one of only two species found on the island of Madagascar (Restio mahonii ssp. mahonii). The sketching of these differences aim to show that they have evolved considerably different mechanisms for survival in different habitats.

Restio mahonii ssp. mahonii

Altitude: 1500-3000m
Habitat: marshy and found in shallow soils over rock
Bedrock: granite
Root structure: stolons
Smoke effect on seed germination: unknown


Thamnochortus spicigerus

Altitude: 0-50m
Habitat: Well-drained, deep coastal sands
Bedrock: alkaline coastal sands
Root structure: rhizome
Smoke effect on seed germination: significantly increases germination

3 Comments:

  • My references:
    1)Linder PH,Eldenas P, Briggse G (2003)Contrasting patterns of radiation in African and Australian Restionaceae. Evolution: Vol.57,No. 12, pp.2688-2702

    2)Linder PH (2002)The African Restionaceae, version 2. Electronic key

    By Blogger Dane, at March 13, 2007 12:57 PM  

  • Hi Dane

    Novel approach I like your subject matter - just a couple of editing issues et al. is in italics with a full stop. Gondwana is Proper Noun so it gets a Capital Letter.

    I really was not looking for anything more than this.

    By Blogger Rich Knight, at March 13, 2007 1:12 PM  

  • Hi Dane

    If I can also add to what Richard has said in the same reference: "(Linder et al, 2003)." Generally a comma before the date of publication suggests that you are referring to Linder as authority. This would be correct if you preceded the reference with a species name. For literature reference I believe (Linder et al. 2003) is ok. Richard or Gwen can confirm this (since it may well be different for plants, in which case you are correct).

    Cheers

    David

    By Blogger davidvaughan, at March 13, 2007 4:56 PM  

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