Could it be Grand Teton National Park’s answer to “Modern Family?” Biologists who have been watching the activities of grizzly bears 610 and 399 noticed last week that one of 399’s three cubs had joined with the two being mothered by 610. A rare occurrence in nature, to be sure — Park Spokesperson Jackie Skaggs says the trade happened on or about last Thursday. Skaggs says the noteworthy event was confirmed by observations of 610 traveling with three cubs in the Willow Flats area of Grand Teton National Park, and later observations of 399 (610’s mother) with just two cubs in an area further north of Willow Flats. Skaggs says bear biologists are not sure what caused the exchange of offspring. Skaggs says it has been observed before in the Greater Yellowstone area, usually triggered by a crisis incident like conflicts with other bears, with wolves, or because of the loss of the mother. The two female grizzly bears and their respective cubs have lingered near park roads over several months time, allowing visitors and local residents an exceptional opportunity to view wild bears in their natural environment. Meanwhile, biologists continue to observe the two families to see if this will be a temporary or permanent situation.