1 / 1

T.Janzen & R.S.Etienne Community and Conservation Ecology Group, University of Groningen

Water height. Million years ago. Proposed lake level of Lake Tanganyika. picture courtesy Jen Reynolds. Paradox of the Cichlids. T.Janzen & R.S.Etienne Community and Conservation Ecology Group, University of Groningen. Introduction

hayley
Télécharger la présentation

T.Janzen & R.S.Etienne Community and Conservation Ecology Group, University of Groningen

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Water height Million years ago Proposed lake level of Lake Tanganyika picture courtesy Jen Reynolds Paradox of the Cichlids T.Janzen & R.S.Etienne Community and Conservation Ecology Group, University of Groningen Introduction The young age and high diversity of the cichlids in the three African rift lakes has amazed biologists, ecologists and evolutionary researchers for many years. Lake Tanganyika is deeper, older, and has a more complex bathymetry than the other two lakes. Ecological and evolutionary theory tells us that it should have the most species of the three lakes, but it has the fewest. Why? • Existing theory ignores external factors • Lake AgeDifferences in age could promote diversity by granting more time for speciation to act, but it also grants more time for extinction to occur. • Water level fluctuations Over the history of the three lakes water level changes have not been rare instances, but rather recurring phenomena. Frequent changes of water level could promote diversificiation by changing lake size. • BathymetryLake Tanganyika is the deepest of the three lakes and consists of three sub-basins that cause the lake to split up when water levels are low. Interaction between the water level and the bathymetry could therefore promote allopatric speciation. • Research questions • How do external factors influence biodiversity? • How do allopatric and sympatric speciation interact during adaptive radiation? • What is the influence of bathymetry on the differences in biodiversity in the rift lakes? • Is sexual selection stronger in lake Malawi compared to lake Tanganyika? Approach To answer these questions we will make use of spatially explicit individual based simulations. We will develop a general model assessing the influence of environment size, environment shape and environment stability on biodiversity. Using this general model we will be able to make predictions on the african rift lake system, incorporate specifics of the african rift lakes and make accurate predictions about current biodiversity estimates.

More Related