What drives specialisation and diversification in island floras?

With Vanessa Cutts, University of Nottingham.

All seminars online. Please contact sue.davis@nottingham.ac.uk for the link. Subject to change.

Part of the Geosciences Seminar Series.

What drives specialisation and diversification in island floras?

Due to their small geographic range, it is theorised that endemic species may be highly specialised to their environment due to local adaptation resulting in a reduced niche breadth.

Oceanic island archipelagos host a disproportionately large number of endemic species, 5-10% of which are highly threatened by extinction. They provide ideal study sites to study endemism as they have endemic and non-endemic species in a geographically defined area. Oceanic islands often reach high elevations, possessing substantial environmental gradients. This suggests that island endemics might be able to tolerate a wide range of environments, introducing scepticism around the idea that they possess distinct ecological features from non-endemic species.

I investigate this using plant functional traits of endemic and non-endemic species along climatic gradients in the Canary Islands. Under the assumption that a reduced range size coincides with a reduced niche breadth and increased specialism, I predict that endemic species show strong integration with their environment (ie strong trait-environment correlations) and occupy narrow climatic ranges.