Wonderful summary on this topic. Makes me wonder if humans are evolving into octopi. Do the same choice of colours in that colourful species line up with the same emotions in humans? Could there be a deeper evolutionary principle at play? With mammal domestication syndromes development of paler or multicolour coats is associated with changes in neural crest development, since melanin and neurotransmitters for fear/aggression come from the same basal metabolic pathway. Same for round ears and short muzzles, which also coincidentally turns up in the kinderschema pattern. Do octopi also use melanin and adrenalin?
Vertebrate species generally tend toward lighter pigmentation in newborn or newly hatched individuals, probably because pigmentation is less necessary in the womb or the egg. A light color is thus mentally associated with helplessness, and a dark color with the opposite. Different species have thus independently evolved dark skin, dark fur, or dark plumage as a threat coloration.
J. Philippe Rushton wrote an article on the correlation between darkness of coloration and male aggressiveness:
"...Ducrest, Keller, and Roulin (2008) reviewed the literature and reported that in 20 wild vertebrate species, darker individuals were more aggressive, sexually active, and resistant to stress than lighter individuals."
Rushton saw the correlation as causal, i.e., melanin increases male aggressiveness. I believe the relationship is more indirect, i.e., natural or sexual selection favors dark pigmentation as a threat coloration in species where the male is highly aggressive. https://evoandproud.blogspot.com/2012/03/dark-coloration-and-male-aggressiveness.html
Definitely look into the domestication syndrome revealed by the Belyaev fox experiments and subsequent genetic analysis. Neural crest development influences pigmentation and reactive aggression based on the same genetic changes, at least to some extent. Likely selection pressures add another layer to the phenomenon.
Red or black clothes for dating profiles!
Interesting conjectures.
Wonderful summary on this topic. Makes me wonder if humans are evolving into octopi. Do the same choice of colours in that colourful species line up with the same emotions in humans? Could there be a deeper evolutionary principle at play? With mammal domestication syndromes development of paler or multicolour coats is associated with changes in neural crest development, since melanin and neurotransmitters for fear/aggression come from the same basal metabolic pathway. Same for round ears and short muzzles, which also coincidentally turns up in the kinderschema pattern. Do octopi also use melanin and adrenalin?
Vertebrate species generally tend toward lighter pigmentation in newborn or newly hatched individuals, probably because pigmentation is less necessary in the womb or the egg. A light color is thus mentally associated with helplessness, and a dark color with the opposite. Different species have thus independently evolved dark skin, dark fur, or dark plumage as a threat coloration.
J. Philippe Rushton wrote an article on the correlation between darkness of coloration and male aggressiveness:
"...Ducrest, Keller, and Roulin (2008) reviewed the literature and reported that in 20 wild vertebrate species, darker individuals were more aggressive, sexually active, and resistant to stress than lighter individuals."
Rushton saw the correlation as causal, i.e., melanin increases male aggressiveness. I believe the relationship is more indirect, i.e., natural or sexual selection favors dark pigmentation as a threat coloration in species where the male is highly aggressive. https://evoandproud.blogspot.com/2012/03/dark-coloration-and-male-aggressiveness.html
Definitely look into the domestication syndrome revealed by the Belyaev fox experiments and subsequent genetic analysis. Neural crest development influences pigmentation and reactive aggression based on the same genetic changes, at least to some extent. Likely selection pressures add another layer to the phenomenon.