Ark II - Episode 1 - The Flies (1976)

Ark II is an American live-action science fiction series, aimed at children, that aired on CBS, beginning and ending in 1976, as part of its Saturday morning line-up. Only 15 half-hour episodes of Ark II were ever produced; however, these episodes were re-run by the CBS television network for several years.
The show's setting was in a post-apocalyptic 25th Century, after Earth's civilizations had been decimated by the effects of waste, pollution, and warfare, falling back to a level comparable to the Dark Ages. The surviving scientists pooled their knowledge and resources, training three young people (and the chimp, who was capable of speech) to search for remnants of humanity, reintroducing lost ideas as they traveled the barren landscape in the high-tech Ark II.
The complete series was once available on DVD, but is now apparently out of print.