Evolution in motion…the on-going case of Darwin’s Finches

Darwin’s finches are some of the best-known species from the Galápagos Islands. They have helped us understand adaptive radiation, the process by which many species can arise from one original ancestor. In the Galápagos Islands, since the colonization of their nearest ancestor 2.75 MYA Darwin’s finches have radiated into the 14 separate species we know today.

Three sympatric species of Geospiza finches in El Garrapatero on Santa Cruz Island are an excellent example of radiation and speciation in process. G.fuliginosa (small), G.fortis (medium) and G.magnirostris (large) ground finches are at the tip of the evolutionary branches and as such they are relatively new species. The on-going variation in their adaptive trait – their beaks – continues to diverge under natural selection pressures. A newly published study by Chaves et al. (2016) found that only 11 out of 32 569 SNP’s (single nucleotide polymorphism) or very minute regions of the genome are related to beak shape and body size on all three species. This is a very small number of SNP’s for such a significant trait.

RAD-Seq is a new technique that allows us to find markers on an entire genome. The authors found that some of the 11 SNP’s are located near genes previously known to be involved in the radiation of beak morphology across Darwin’s finches, but others are not. So some may influence divergence in the macro (genera) and in the micro (speciation) scales. How these are expressed is due to a combination of breeding selection and/or environmental pressures.

In songbirds speciation involves species-specific song learning and physical recognition. Should these queues be confused, they could act as reproductive barriers. But if appearance is too similar or the wrong song is imprinted it can lead to hybridisation. Interestingly G.fortis birds have the genetic and morphological evidence of hybridisation between these three species. Genetic compatibility exists and speciation in this case is as yet incomplete. This can increase genetic variation in either direction it goes and “it can mediate early stages of ecological speciation at the tips the radiation”. Natural selection has acted upon Darwin’s finches during our lifetimes and it will continue to do so given the ever-changing environmental conditions. It will never cease to be fascinating seeing how genes and natural environmental unpredictability keep evolution in motion.


Chaves, J.A., Cooper, E.A., Hendry, A.P., Podos, J., De León, L.F., Raeymaekers, J.A., MacMillan, W.O. and Uy, J.A.C., 2016. Genomic variation at the tips of the adaptive radiation of Darwin’s finches. Molecular Ecology

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In 2022, the Galapagos Science Center (GSC) and the broader UNC & USFQ Galapagos Initiative will celebrate its 10th Anniversary. We are proud to announce the World Summit on Island Sustainability scheduled to be held on June 26–30, 2022 at the Galapagos Science Center and the Community Convention Center on San Cristobal Island.

The content of the World Summit will be distributed globally through social media and results documented through papers published in a book written as part of the Galapagos Book Series by Springer Nature and edited by Steve Walsh (UNC) & Carlos Mena (USFQ) as well as Jill Stewart (UNC) and Juan Pablo Muñoz (GSC/USC). The book will be inclusive and accessible by the broader island community including scientists, managers, residents, tourists, and government and non-government organizations.

While the most obvious goal of organizing the World Summit on Island Sustainability is to celebrate the 10th Anniversary of the GSC and the UNC-USFQ Galapagos Initiative, other goals will be addressed through special opportunities created as part of our operational planning of the World Summit.

For instance, we seek to elevate and highlight the Galapagos in the island conservation discourse, seeking to interact with other island networks in more obvious and conspicuous ways to benefit the Galapagos Islands, the UNC-USFQ Galapagos Initiative, and the world. We will seize the opportunity to further develop the I2N2 – International Islands Network-of-Networks. Further, we wish to highlight and emphasize multiple visions of a sustainable future for the Galapagos Islands and we cannot do this alone. Therefore, engaging the Ecuadorian Ministry of Environment, the Ministry of Tourism, the Government Council of Galapagos, the Galapagos National Park, and local Galapagos authorities, including government and non-government organizations and local citizen groups, is imperative.

The Galapagos Science Center on San Cristobal Island, Galapagos

Borrowing from Hawaii’s and Guam’s Green Growth Program and the Global Island Partnership, we wish to examine existing global programs that emphasize island sustainability and their incorporation into life, policies, and circumstances in the Galapagos Islands. We will also seek to enhance our connections with the institutional members of our International Galapagos Science Consortium and expand the Consortium through the recruitment of other member institutions. We will also work to benefit islands and their local communities by working with citizen groups as well as important NGOs who seek to improve the natural conditions in the Galapagos and diminish the impact of the human dimension on the future of Galapagos’ ecosystems.

Lastly, we will use the World Summit to benefit UNC & USFQ and our constituencies through a strong and vibrant communication plan about the World Summit, creating corporate relationships as sponsors, identifying funding goals through donors, and benefiting our study abroad program for student engagement in the Galapagos Islands. We plan to develop and issue a Galapagos Sustainability Communique after the World Summit that includes the vision and insights of all its participants for a sustainable Galapagos with applicability to global island settings.

We are eager to hear your perspective and have you join us at the World Summit on Island Sustainability!