Valentine's Day edition

For awhile I had a tradition, on Valentine's Day, of linking to Jennifer Ouellette's "Love among the equations" fun tribute to her husband, physicist Sean Carroll. I haven't done that for awhile, so for anybody who's never seen it, seems like a timely jaunt down memory lane: 
https://blogs.scientificamerican.com/cocktail-party-physics/love-among-the-equations/

Meanwhile, Rob Eastaway yesterday tweeted out this chart of "popular" birthdays, noting that you can also deduce other 'popular' days (of a sort) by subtracting 9 months from the chart results:
https://twitter.com/robeastaway/status/1227896654214418433

...and lastly, just for today, something we can all relate to, the mating dances of a couple of our avian friends: