The Age When Birds Ruled The Earth

SciBlogs editorial staff looks at the meaning of dominance. Did dinosaurs ever really rule the Earth? Did they ever stop? And what does it mean to be "dominant"?

i-60f448650912c047098b87dcba7c7242-birds.jpg

Two Willet birds in silhouette (Tringa semipalmata; formerly Catoptrophorus semipalmatus) on Morro Strand State Beach. From Flickr, by mikebaird

Yesterday on Not Exactly Rocket Science Ed talked about a new paper in the journal Science that looks at the diversification of large vertebrates after the Triassic/Jurassic extinction event. In simple terms, how did dinosaurs take over the Earth? I think the article and Ed's response begs an interesting question. Namely, what does domination mean? Ed says "Today, living dinosaurs - the birds - still rule our skies and back in their heyday, they were the dominant back-boned animals on land for millions of years." Were the dominant back-boned animals? Today birds are without a doubt the most diverse terrestrial vertebrates and total bird biomass exceeds mammal biomass by a long shot. So who's really dominating whom? For many birds, we clean their shit, help them breed and feed them. Sounds like they're the ones in charge. The point isn't that we need to free ourselves from our avian oppressors. Rather, the concept of dominance doesn't seem to be very scientific. Biodiversity? Sure. Biomass? Why not. But dominance? Ruling the Earth? Those are terms that don't really mean anything in a scientific sense because, in the end, as Stephen Gould put it, isn't every age the Age of Bacteria anyway?

Tags

More like this

Some 230 million years ago, giant reptiles walked the Earth. Some were large and fearsome predators; others were nimble and fleet-footed runners; and yet others were heavily armoured with bony plates running down their backs. Their bodies had evolved into an extraordinary range of shapes and sizes…
tags: Western Willet, Tringa semipalmata, birds, mystery bird, bird ID quiz [Mystery bird] Western Willet, Tringa semipalmata, photographed at Galveston East Beach, Texas. [I will identify this bird for you in 48 hours] Image: Joseph Kennedy, 25 August 2009 [larger view]. Nikon D200, Kowa 883…
tags: Eastern Willet, Catoptrophorus semipalmatus semipalmatus, birds, nature, Image of the Day Eastern Willet, Catoptrophorus semipalmatus semipalmatus, at Bolivar Flats, Texas. Image: Joseph Kennedy, 6 June 2008 [larger view]. Nikon D200, Kowa 883 telescope with TSN-PZ camera eyepiece 1/640s…
tags: Western Willet, Catoptrophorus semipalmatus inornatus, birds, nature, Image of the Day Western Willet, Catoptrophorus semipalmatus inornatus, at Bolivar Flats, Texas. The bird on the left is in alternate (breeding) plumage while the bird resting on the right is in basic (winter) plumage.…