Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: [Phys-L] Thermodynamic Crows

Interesting ideas. However, most bird behavior and appearance has to do with mating with prompts coming from appearance and behavior. So another question might be, considering that crows are all black what are the mating prompts that allow them to take the advantages you have suggested and why haven’t other birds evolved as the crows have?

stay well


Joseph J. Bellina, Jr. Ph.D.
Retired Professor of Physics
Co-Director, Northern Indiana Science, Mathematics, and Engineering Collaborative (NISMEC)
Consultant I-STEM Network

On Aug 7, 2020, at 7:10 PM, Bill Norwood via Phys-l <> wrote:

Hi Phys-L Thinkers

I am figuring out why crows are all black.

Perhaps if I write something that DOES make sense, it will combine with the thoughts of others to help explain this black crow phenomenon.

1. Intelligence: Crows are credited with a high level of intelligence:
1a. If a human is hostile to one of them, they will have a meeting where all crows become informed about this particular human, including how to identify the human.
1b. If a crow gets killed on a particular farm, that farm will be avoided in all future migrations.
1c. Crows can recognize individual crows as well as individual human faces.

2. Digestion: Crows are omnivores and are known to eat anything. That would lead to a great variety in energy expended in digesting a particular meal. That would in turn lead to a great variety in how much heat is given off by the digestive system and to a need to efficiently expel heat in the case of a heavy meal. Black would efficiently and quickly expel the heat.

4. Warming and Cooling: A crow finds himself cold standing in a tree, then flies out into the sunlight and quickly becomes warmed, because his black coat is also the most efficient heat absorber. So the crow may have a survival advantage over other birds and small animals in cold or hot climates. Said differently, the crow may be occupying a predatory niche.

Ok, it’s your turn - any ideas?

Bill Norwood
Retired from,
U of MD at College Park, Physics Dept
Sep 2018

Sent from my iPhone
Forum for Physics Educators