Two Sunny HIkes and House Finches

Friday and today were just glorious days.  I love the sky in winter, it has that deep blue color to it.  By April it will be washed out and drab.

Friday we did our new stair master trail and thoroughly exceeded our aerobic thresholds.  It was good.  It's as difficult as the trail up to Golden Gate, but the surface is better and easier on the feet.

This was taken from the John Krein trail.  That peak over on the right is on our list for this year.  Standing up there is very lovely.

Today was a day for contrails.   They're  faint, but you can see four contrails next to each other.  They were too high to identify the planes, but Jim suspects they're large and military.  Fighters don't contrail that much, so multiple engines are likely.  Commercial planes don't fly in a formation like that.

We hiked up the trail that goes towards Ringtail Ridge.  It's another stair master trail.

Here is an interesting article about birds.  It's about urban bird feeders and how they affect birds' development.  I've cut and pasted a paragraph from the article.

So when one of Badyaev’s undergraduate students, Clayton Addison, noticed that the male finches on campus in central Tucson were not singing a rapid trill that’s essential for attracting females in the nearby desert, the lab was able to dig into the data for answers. Comparing the beak sizes, bite forces, and diets of the two populations, the researchers showed that the urban finches rely so heavily on feeders that their beaks have adapted: they’ve become longer and deeper to accommodate the sunflower seeds typically on offer, which are much larger and harder than the small cactus and grass seeds that rural finches eat. This adaptation has altered not only how urban males sing, but also what urban females prefer in a mate. It’s a pattern that Badyaev has since found in other places where finches live in the shadow of humans, the same large beaks arising from a surprisingly diverse array of developmental pathways. Such varied routes to an identical end—a beak strong enough to crack sunflower seeds—may be one way that nature hides variability from the swinging axe of natural selection.

We had house finches at the RV park where we used to stay in Tucson.  I've heard them sing this song, it's kind of sad that the urban birds won't sing it anymore.