Wild Thing! is a show of two halves. The stronger second half engages with the Sixth Extinction, the process that is happening at this moment and predicts the doom of the current biosphere, fitting snugly into the live art strategy of discovering a personal ritual to mark out the artist’s research. This section is fascinating and beautiful, the stage scattered with bones and a sheet that lists those animals that have become extinct, as well as presenting the artist’s literal journey to a performance from Scotland to Scandinavia on foot. The seriousness of the subject is marked by solemnity of performance, an attempt to communicate the tragedy of environmental collapse.

Unfortunately, the first half (the comedy bit) is lazy, a kind of extended improvisation on the various species based on their names rather than their actual biology. Leaping between characterisations, it has the feel of a rehearsal strategy, played for laughs and going on for too long. It also fails to connect with the second section’s darker tone, giving the show a comic rather than thoughtful energy that outstays its welcome. With a powerful soundscape and reflective approach to an important matter, the show contains some seeds of excellence, but lacks dramaturgical discipline.

Wild Thing!, Summerhall, until 25 August, 1.30pm; main picture: Alex Brenner.