A scientist studying tropical birds in Panama notices that the environment of the islands of Bocas del Toro is more like the environment of small islands in Honduras than that of the mainland of Panama. She hypothesizes that birds in Bocas del Toro will share more traits with birds on the islands in Honduras than they will with birds on mainland Panama. She records her observations of bird species in all three locations and concludes that the species on Bocas del Toro are more similar to species on the nearby mainland. This conclusion supports which of the following statements?

A Biotic factors in the environment are the primary factors determining traits in tropical birds.
B The wings of the different birds are variations on a common anatomical plan.
C The birds of Bocas del Toro evolved from immigrants from the mainland.
D The birds of Bocas del Toro evolved from immigrants from Honduras.

A scientist studying tropical birds in Panama notices that the environment of the islands of Bocas del Toro is more like the environment of small islands in Honduras than that of the mainland of Panama. She hypothesizes that birds in Bocas del Toro will share more traits with birds on the islands in Honduras than they will with birds on mainland Panama. She records her observations of bird species in all three locations and concludes that the species on Bocas del Toro are more similar to species on the nearby mainland. The similarity in the traits can be because the birds of Bocas del Toro evolved from immigrants from the mainland.