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Opsin gene polymorphism predicts trichromacy in a cathemeral lemur
Carrie C Veilleux1, Deborah A Bolnick
1Department of Anthropology, University of Texas at Austin, Austin, Texas 78712-0303, USA. cveilleux@mail.utexas.edu
American Journal of Primatology
|October 7, 2008
Summary
Polymorphic trichromacy, the ability to see a wider range of colors, is now found in cathemeral (active day and night) lemurs. This challenges the idea that only diurnal animals can evolve this trait.
Area of Science:
- Primate vision evolution
- Molecular genetics
- Color perception
Background:
- Polymorphic trichromacy, enabling enhanced color vision, has been documented in diurnal strepsirrhines.
- Existing hypotheses link the evolution of trichromacy to the transition to diurnal activity in primates.
- Cathemeral lemurs were presumed to lack the necessary M/L opsin gene polymorphism for trichromacy.
Purpose of the Study:
- To investigate the presence of M/L opsin gene polymorphism in cathemeral lemurs.
- To determine if trichromacy exists in cathemeral Eulemur species.
- To re-evaluate hypotheses on the evolution of trichromacy in strepsirrhines.
Main Methods:
- Sequencing of the M/L opsin gene in ten cathemeral blue-eyed black lemurs (Eulemur macaco flavifrons).
- Analysis of the M/L opsin gene sequence for polymorphisms at critical amino acid positions.
Main Results:
- A polymorphism identical to that found in trichromatic strepsirrhines was identified in Eulemur macaco flavifrons.
- This finding indicates the likely presence of polymorphic trichromacy in at least one cathemeral Eulemur species.
- The results challenge the necessity of strict diurnality for the evolution of trichromacy.
Conclusions:
- Strict diurnality is not a prerequisite for the evolution of polymorphic trichromacy in lemurs.
- The presence of trichromacy in cathemeral Eulemur species necessitates a re-evaluation of current evolutionary hypotheses.
- The distribution of opsin alleles may suggest either independent acquisitions or a common origin of trichromacy in lemurids and indriids.
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