I had a quick look online. There seems to exist many different website of database archiving. Some data might be free of charge while some others might not be. I found things such as Dryad, TreeBase, DataOne or GeneBank. I think that several journals (American Naturalist, Molecular Ecology, Science and Nature for examples) force their authors to make their data available
Can you make a short review of what different database exist, what are their properties (what kind of data, what license and fees) and how to seek for data (are datasets associated to keywords or do we have to look for a paper and then look for their data).
Imagine for example, you are looking for SNP data of a spatially explicit population that recently underwent a range expansion (might be too accurate, you may want to drop down some specifications). How would you go about to look for this kind of data? (No need to pull out data but only to describe a procedure).