The parasitical horsehair worm grows and grows for two to three months inside its host until it takes up most of the body – then engineers its way out.

In a look ahead at a week of Cambridge and Somerville events, we go from Artbeat in Davis Square to AfroVybe in Union Square with pauses for kayaking on the Charles, a reading from Colson Whitehead, a Barbie drag show, a Women of the World music and dance showcase and much more.

I realized that in my irritation and fear I’d lost sight of something: You don’t get the blessing without the risks. That is, bugs aren’t bugs – they’re a feature.

Because of the name, you might think the red admiral butterfly is somehow associated with the sea or sailors or seafaring – but it was originally called red admirable, presumably because it was a butterfly with many qualities to be admired.

Do you remember chasing flickering fireflies as a kid? In Massachusetts, there are at least 20 species of them, and you should be able to see them here now.

In a look ahead at a week of Cambridge and Somerville events, there’s a Nature in the City Festival, Italian Bel Canto Opera concert and Summer Boston Celtic Music Fest, “Beach Too Sandy, Water Too Wet” podcast recording, silent headphone party and more.

It’s young male black bears that most often make their way into residential neighborhoods in June and July; older males can be as heavy as 600 pounds.

Look for viceroys now – they reach peak numbers in mid-June and again in late July – but don’t mistake them for the monarch butterflies they ape.

Indigo buntings are easier to spot than many birds because the blue male stands out against the trees and likes to find the highest perch from which to sing.

Houseflies are pests, but are here because they have followed humans and their waste around the planet – and can be amazingly hard to hit with a swatter.