After about the fifth one sighted, we knew it was going to be a good vermilion flycatcher day. Of course our main highlight for the day was the giant tortoises that were roaming around on Steve Divine's farm in the highlands of Santa Cruz. But how can one resist getting just one more photo of the brilliant red bird that, like most of the wildlife here in Galapagos, got closer and closer to us.
The vermilion flycatchers, Pyrocephalus rubinus, that exist in the Galapagos seem to have been here for a long time. But how long? We can find this species on the mainland of Ecuador. In fact, on the continent, it is quite widespread and is found as far north as Arizona. In Galapagos these flycatchers are restricted to the moist highlands of the larger islands. The island flycatchers show a slight difference from their continental counterparts: the females here have yellow underneath. On the mainland the females have pink and white underparts.
How do we define the specific status of this bird? Does this difference in plumage make the island bird a different species? Or a different sub-species or race? This is the question we are always asking ourselves with many of the animals here. As there are such subtle differences between populations from island to island, and from island to continent, taxonomists find that at this level, species become much harder to separate. Even the difference between species, sub-species and race is questionable! Occasionally, the experts will present papers, and these days they often contain hard evidence at the DNA-level, which separate these populations. But when you get to such a subtle level, it becomes evident that the animals are in a continuous flux, with new 'species' being discovered every year.
It is this subject that makes Galapagos such a great evolutionary laboratory. Here scientists have an excellent opportunity to study even well known animals like the vermilion flycatcher, so that we can understand and define better the species.
