That's true, if anything the new techniques should theoretically make it cheaper, if you are ever interested in the history of the science of it (though light on the politics/economics), this is a pretty cool book:

They grow up so fast...

A pair of Canadian eagles

Most (all?) birds on the other hand have 4 color sensitive opsins, ranging into the UV. Researchers can train hummingbirds to detect feeders with and without sugar using LEDs at wavelengths the researchers can’t differentiate with their naked eyes www.pnas.org/doi/10.1073/...

Camera sensors use different filters to detect different wavelengths. To differentiate wavelengths, cone cells must express one opsin type, perhaps X inactivation explains this in new world monkeys, but only for MW and LW opsins and this doesn’t explain regulation in catarrhines and howler monkeys.

Researchers observed similar ratios in squirrel monkeys here, though the numbers are small: link.springer.com/article/10.1.... Females are still only trichromatic, since they can’t inherit more than two opsins. A question for another time is how these genes are regulated.

This should result in 50/50 trichromatic/dichromatic females. But what happens when mutations create opsins on the same locus that are sensitive to new unique wavelengths? Selection will favor the rarest allele until each composes 1/3 of the frequency. And 2/3 of females will be trichromatic!

Males, with only one X chromosome, can’t inherit both. Females must inherit two DIFFERENT opsins from their father and mother to be trichromatic. If trichromacy gives a selective advantage a form of “frequency dependent selection” occurs, the less common an opsin, the more advantageous it is.

In between these two extremes are new world monkeys. Except for howler monkeys, all male new world monkeys are dichromatic and a fraction of females are trichromatic. This is due to their MW and LW opsins residing on the same locus of the X-chromosome.

Most mammals only have dichromatic vision, with their short wavelength opsin on an autosomal chromosome and their long- or medium-wavelength opsin on their X-chromosome. In humans two amino acids affect the color sensitivity of OPN1MW and OPN1LW, at positions 277 and 285.

Trichromatic vision means an individual can detect colors along three axes. The axes are constructed from cone cells expressing unique opsins. In humans these opsins are called OPN1SW (short-wavelength), OPN1MW (medium-wavelength) and OPN1LW (long-wavelength).

Catarrhine primates, including apes and us, have 3 molars, 2 pre-molars, 1 canine and 2 incisors per quadrant. With some exceptions platyrrhines have the same dentition but with 3 pre-molars instead of 2. Catarrhine primates also have trichromatic vision.

Thread: Color vision and primates; an excuse to share wildlife photos. There are two main groups of monkeys, new world or flat-nosed (platyrrhine) monkeys and old world or “down”-nosed (catarrhine) monkeys. “Monkeys” as a group are paraphyletic, since the group artificially excludes apes.