F/7.1, 1/200, ISO 250.

American Goldfinch 

How do cows do mathematics?

They use a cow-culator.

Interesting Fact: American Goldfinches are active, acrobatic finches that balance on the seedheads of thistles, dandelions, and other plants to pluck seeds. They have a bouncy flight during which they frequently make their po-ta-to-chip calls. Although males sing exuberantly during spring, pairs do not nest until mid-summer, when thistles and other weeds have gone to seed. Goldfinches do not join other songbirds mobbing predators. ( https://www.allaboutbirds.org/guide/American_Goldfinch/lifehistory )