Science Quote by Peter R. Grant

In Peter R. Grant's hands, this neat, almost sleepy sentence is doing far more work than it appears to. "Closely related" sounds like a casual nod to taxonomy, but it smuggles in an argument about what relatedness really means: not just shared feathers or beak shapes, but shared genomic architecture. The adverb "also" is the tell. It's quietly polemical, insisting that chromosome patterns belong on the same evidentiary tier as morphology, behavior, and ecology. Grant isn't merely describing birds; he's tightening the bolts on evolutionary inference.

The intent is to normalize chromosomal similarity as a predictable consequence of common descent. That's a rebuttal-in-a-whisper to older habits of classifying species primarily by visible traits, where convergent evolution can make strangers look like siblings. Chromosomes, by contrast, carry a different kind of signature: rearrangements, fusions, and inversions that tend to accumulate with time and can act like a molecular clock with caveats. Grant's phrasing invites the reader to see cytogenetics not as a niche technicality but as corroboration, the backstage paperwork that matches the public story.

Context matters because Grant is inseparable from finches and field biology: evolution observed, measured, argued over in real ecosystems. In that world, "chromosomally similar" hints at constraints and possibilities, too. If close relatives share chromosomal layouts, hybridization and gene flow become more plausible; if they don't, reproductive barriers harden. The line reads like a small factual bridge between Darwin's visible variation and the modern genome's invisible bookkeeping.