Rosemary and Peter Grant have devoted 40 years of their lives to studying the finches of the Galapagos Archipelago, the birds that inspired Darwin's theory of evolution. The couple´s work has allowed them to prove that evolution can take place at a much faster pace than previously believed; in less than a decade, the beaks and bodies of these birds can transform to adapt to environmental changes.
The jury of the BBVA Foundation Frontiers of Knowledge Award
in the Ecology and Conservation Biology category praised the work of the Grants for providing 'the most complete account of how evolution works
in nature,' and 'elucidating the mechanisms through which genetic diversity is preserved and new species originate
The findings of this British biologist couple have enormous implications for the conservation of threatened species. The jury's citation underscores how their work 'adds an evolutionary perspective to conservation biology by recognizing that rapid evolutionary changes can occur
after the arrival of invasive species (including humans) or in response to catastrophic events
A tent in a volcano crater
In 1973, Rosemary and Peter Grant arrived in the Galapagos Archipelago and settled on the small island of Daphne Major
- the crater of an extinct volcano, with barely enough space to pitch a tent. Encouraged by their first observations of the behavior of local finches, they decided to return for a few months each year to tag and measure the birds, and record their behavior. And so the two continue, now more than eighty years of age, with their next visit to Daphne scheduled for March this year
As Peter Grant explained on the phone yesterday after hearing of the award, 'We chose Darwin's finches because they form a group of 18 species living in an environment where the human imprint is almost entirely absent. Also, in the Galapagos the climate varies considerably from one season to another. You also have very wet followed by very dry years, and that led us to think that we might find clues as to what environmental factors were driving the maintenance of communities and the generation of new species in those communities.'
Evolution can happen in just ten years when the environment changes'
The decision, it turned out, was a wise one. In 1977, after several years measuring characteristics such as the size of the birds' bodies and beaks, they were able to observe what befell the finches during a period of severe drought: the environmental changes caused by the shortage of water favored birds with beaks of a certain shape
, while the rest died off in large numbers. As a result, some genetic traits, but not others, were passed on to the next generation.
'Our research in the Galapagos showed that evolution can happen in just ten years when the environment changes,' explains Rosemary Grant. 'And by persisting in our study for forty years we discovered that this is not just a singular event, but that evolution recurs.'
Throughout their career, the Grants have incorporated new knowledge in molecular and genetic biology into their study data, and have been able to verify that the things they were seeing in the field and recording in their notebooks were also occurring at genetic level. Thus, they've been able to document the emergence of what they call 'a new lineage
' of finches
. As Peter relates, 'our second big finding was that two species, under certain circumstances, can hybridize and produce a third in as little time as three generations
For Rosemary, 'this shows that we can study the process of species generation in our own lifetimes, provided we pick the most suitable places to study. And we can follow the consequences of those events. Darwin was concerned that the evidence for change was not obtainable within a human lifespan
We need to think more broadly about how to conserve biodiversity in general, and not just focus on rhinoceroses, tigers or elephants'
The Grants' work has been fundamental in connecting the study of with evolution with ecology
and as such, has major implications for biodiversity conservation. 'We need to think more broadly about how to conserve biodiversity in general, and not just focus on rhinoceroses, tigers or elephants. Unless we make a serious effort to preserve the habitats where these endangered species live, it will be very difficult to preserve biodiversity,' says Peter.
Conservation of the Iberian lynx and coral reefs
The insights from the Grants' work are being put into practice to conserve the Iberian lynx, following a strategy that consists of accelerating a species' natural evolutionary process to favor certain traits that improve its resilience to changes in the environment. As Pedro Jordano, research professor at the Doñana Biological Station, explains, in Doñana 'we have introduced individuals
with better adapting genotypes, that, for instance, exhibit better resistance to diseases
such as feline leukemia virus.'
Another conservation strategy now in development that draws on the Grants' work is the identifying of the coral varieties most resistant to changes in the reef environment
, so as to hasten the system's recovery after alterations such as increases in temperature, water acidification, etc. The introduction and propagation of hardier strains favors a speedier adaptation to these drastic environmental changes.