Evolutionary ecology

Ranga and guppies reach a happy end

Ranga Jayawickrama has successfully completed his Master examination. EvoFish congratulates!

Ranga Jayawickrama and Christophe Pelabon discussing during the Master...
Ranga Jayawickrama and Christophe Pelabon discussing during the Master examination
Mikko Heino

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Ranga has been working with his master project on morphological traits in guppies since winter 2012. The project reached a happy end with the examination of Ranga's thesis "Consequences of size-dependent harvest in guppy: study of morphological traits and their heritability" on Friday, June 7. The external examiner was Christophe Pelabon from NTNU.

Ranga has found that during the early part of our guppy experiment, the experimental fishing regimes have not lead to evolution of different morphologies. This is probably because the selection pressure in the beginning was not very strong and because of the short time frame involved (slightly more than one generation). However, some adaptation to captivity has taken place in terms of an elongated caudal peduncle and a shortened caudal fin. Moreover, the common garden experiments suggest that these changes have a genetic basis.