Why Do Some Black Cats Appear Brown

Black cats with the recessive "agouti" gene appear reddish or cinnamon in sunlight. 

Agouti Gene 

Sunlight triggers increased pheomelanin production in agouti black cats, creating a warm brownish hue.

Pheomelanin Production

Full sunlight alters ratios of eumelanin & pheomelanin in agouti black cats, making reddish tones visible.

Melanin Ratios 

Genetically, cats that shift color in the sun are not "true" black cats. They have a modified black coat.

Not True Black Cat

To our eyes, the coats seem to change color, but it's just a reveal of underlying pheomelanin in the fur.

Perceived Coat Changes

The cat's actual hair color remains genetically unchanged. Sunlight simply makes hidden red/brown hues perceptible.

No True Color Change  

The coat color change can be quite dramatic on some cats, going from black to cinnamon or chestnut. 

A Striking Effect

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