Alison Kim Shan Wee
Dept. of Biological Sciences, NUS
Wed, 16 Oct 2013: 10.00am
@ DBS Seminar Room 1, S2 Level 4
Supervisor: Assoc Prof Webb, Edward Layman
All are welcome
“Mangroves are threatened globally by land conversion, habitat degradation and climate change. The challenge in maintaining sufficient genetic diversity and evolutionary potential within species in an increasingly fragmented landscape places great importance on the genetic connectivity among populations. This thesis investigated the effects of reproductive traits, physical barrier and ocean currents on the genetic connectivity of four major species from the Malay Peninsula (MP)—Avicennia alba, Sonneratia alba, Bruguiera gymnorrhiza and Rhizophora mucronata.
A comparative analysis was conducted to examine the effects of physical barrier and reproductive traits on genetic connectivity. Convincing evidence from the study showed that the MP is a selective “filter” to gene flow—genetic discontinuity was more distinct in A. alba and S. alba than in B. gymnorhiza, and not at all in R. mucronata. The relative propagule dispersal potential across species provided a compelling explanation for the genetic pattern observed.
A more detailed study involving ocean circulation simulation on R. mucronata provided evidence that the gene flow in R. mucronata is maintained by ocean current-facilitated propagule dispersal. This thesis offered valuable insights on the factors influencing gene flow among populations, which are useful in understanding how increasing anthropogenic disturbances may threaten mangrove communities.”