Misc: What small fish, often tinned, was named after a Mediterranean island?

Questions

What reptilian feature evolved in feathers?

What restaurant chain had served forty five thousand million hamburgers by 1983?

"what is it that walks on four legs, then on two legs, & then on three"?

What rifle accessory originated in Bayonne, France, in 1641?

What river does the Grand Coulee Dam dam?