In the Noon Universe created by Arkady and Boris Strugatsky, the foundlings are a group of 13 humans, who evolved out of the embryos stored in the "sarcophagus". The embryos were discovered on December 26, 2137 by Boris Fokin's group of explorers on an unnamed planet in star system EN-9173. These events are described in the novel Beetle in the Anthill.
In the late December 2137 an explorer group led by Boris Fokin discovered and obtained a permission to study an artificial underground cave, presumably, built by Wanderers. After entering the cave, Fokin's men discovered a strange machine which they called the "sarcophagus" (because of its visual similarity to ancient ritual coffins). The calculated age of the device was approximately 40 to 45 thousand standard years and it was soon discovered that the Sarcophagus is connected to a planet-wide network of energy generators providing it with energy.
The true shock came when it was uncovered that the Sarcophagus is, in fact, a sophisticated incubator containing 13 fertilized, but latent human egg cells. Shortly after that Gennady Komov, the director of the expedition to EN-9173, ordered to classify any information on this discovery, therefore nearly nothing about it was known to the public.
Immediately after the discovery of the embryos, Komov informed the Earth World Council and demanded further instructions. The reactions of the Council were very different, but in the end Rudolf Sikorski (already being in chief of COMCON-2) demanded that they decide whether they destroy the device and the embryos or activate them. Leaving things as they were, according to him, was not an option.
Kirill Alexandrov, one of the youngest Council members, suggested that these 13 humans were, in fact, not humans but Wanderers and, since no one could contradict him in this, that the Sarcophagus was a safe containing their gene pattern. Because it was, thus, none of Earth's business he proposed "leaving things as they are" and abandoning the EN-9173 system immediately.
August-Iogann-Maria Bader argued that the sarcophagus was built by the Wanderers to preserve actual human embryos. According to him, Wanderers may have created this gene storage 45,000 years ago to preserve human species in case of a catastrophe that would wipe out the whole race.