3 novellas.
Gregory Benford: nice concept, but he cut too many corners to make the grandiose ending satisfying. The tension builds, and then dissipates too quickly, as we read about the aliens and their manipulations of sasquatch.

Clifford Simak: I like Simak, but this story is a bit make-shift. A photographer from the future records some juicy scenes from the past and then gets eaten by a bear.

These two stories are mildly entertaining and worth a pleasant read…but Norman Spinrad’s story caps the bunch and compensates for any weaknesses of the others—how should mankind react against a universe that has no other life forms…anywhere? ( )

Three novellas.
The title story, "Threads of Time" by Gregory Benford, has a resourceful central character, a female lunar surveyor/archaeologist who begins by hacking her way out of a damaged vehicle to explore the alien defense system which has attacked her. The tension between the scientists and the New Sons, a religious cult with growing political clout whose basis is not really explained, is presumably intended to recall contemporary tension between science and religion in America. There is a parallel story tracking Bigfoot through the American forests, and the whole thing boils down to an extended and rather old-fashioned variation on a central idea of "2001: A Space Odyssey" (ancient alien artifact reveals contact with prehistoric hominids).
"The Marathon Photograph" by Clifford D. Simak is basically a meeting with a group of time travellers, and a chance for a bitter conversation about humanity's bleak future.
"Riding the Torch" by Norman Spinrad gave me the most pleasure. Humanity has had to abandon a war-ravaged Earth and head out into the stars in a flotilla of spacecraft seeking another planet, though developing their technology to such an advanced stage that they seem not to need one, except psychologically. Among the decadent high-tech socialites, Jofe D'Mahl, an artist in an operatic/cinematic genre of sensory stimulation, is challenged by one of the cult-like caste of planetary survey teams to confront the void, and then communicate the meaning (or futility) of human existence back to the rest of the population.
MB 6-x-2020 ( )