By Nick

A sphere of coccoliths under a scanning electron microscope. Created by the coccolithophore Emiliania huxleyi. Image from the Encyclopedia of Life.

Coccolithophores are tiny single celled planktonic organisms that live in the oceans. They have tiny armoured calcium carbonate plates known as coccoliths. Whilst still present and abundant today, during the time of the dinosaurs there were trillions upon trillions of these organisms living in the warm shallow oceans that pervaded much of the planet. Coccolithophore elections during the Cretaceous were hotly contested. And these notoriously liberal voting critters are still influencing voting patterns today.

Its just a pity they aren’t registered to vote, otherwise the trillions of coccoliths could easily swing an election. However they are doing their bit, through a curious bit of geology, and history, that leads to a swath of blue voting counties across the deep south of America. I came across this gem of a blog post via a couple of American geologist friends, it’s well worth a full read here, but here’s a summary.

A swath of blur voting counties stretch across the American South. Image from NPR, credited to Matt Stiles

What do these critters do now? Well, the trillions of coccoliths descended to the sea floor when the coccolithophores died. And these little shells became what we know of today as chalk. The coccoliths were most abundant on the Cretaceous coastline of the southern united states

This chalk then creates organic rich, black soils. These organic rich soils produce excellent cotton. So the most productive cotton plantations in the United States run in a band, along the rich soils, above the chalk, where the American coastline was during the Cretaceous.

Back in the days of slavery these successful plantations would have had the most slaves. Slaves who would then be freed. And eventually, the descendants of these slaves would be able to vote. Counties with the highest African-American population still lie across this former coastline.

And with African-American’s more likely to vote Democrat rather than Republican, hey presto, a swath of blue voting counties, following African Americans, who follow former cotton plantations, which follow rich soils, which follow chalk, which follow coccolithophores. Very neat, very clever.

Do check out the full post at – with lots of good graphics: