Sexual display

Someone thought that I was a suitable receptacle for the collection of curious facts about birds assembled at reference 1. Assembled by a former journalist who writes on a good number of subjects - which, despite the access to information now offered by the Internet, leads me to wonder how careful he has been about checking his facts. Perhaps one ought to check for oneself before putting much weight on them.

Today, I offer one of his facts without any such checking.

It seems that the colourful beaks of puffins are all about sexual display and are sported by both sexes: the bigger and better your beak, the bigger and better mates you are going to attract. One wonders whether puffins have learned to cheat, with some very scrawny specimens sporting very fine beaks - although thinking with my fingers, it may be that evolution has thought of that and makes sure that the quality of sexual display is tightly coupled with evolutionary fitness, a tight coupling which makes cheating difficult. But a coupling that us humans, with our big brains, have learnt to uncouple, the unfortunate effects of which can be seen the world over. Still thinking with my fingers, it also strikes me that modelling of all this is going to be difficult and complicated, with all kinds of tricky feedback loops, even with our big computers.

In any event, the colourful beaks of puffins are really beak cases, discarded at the end of the mating season, leaving the rather small and plain, proper beak.

PS: with thanks to reference 3 for the image. And where the story about beaks is not quite the same as that offered by Edworthy. Views?

Reference 1: The curious bird lovers' handbook - Niall Edworthy - 2009 or 2017. Two dates as first publication was under a different name.

Reference 2: https://beta.companieshouse.gov.uk/company/04741307/filing-history. In the absence of a personal web site, read all about his financial affairs. But he can relax in the knowledge that I can't make head nor tail of them. Help?

Reference 3: https://www.nordicvisitor.com/blog/5-things-may-not-know-puffin/.