PERTH, Australia, Dec. 22 (UPI) — Out-of-touch grandparents, drunken uncles, mischievous cousins ─ the holidays are the time when relatives do their best to test the limits of good cheer.
If you feel like avoiding your family this time of year, Australia’s bobtail lizards, Tiliqua rugosa, wouldn’t blame you.
As new research reveals, they tend to avoid their relatives all year long. After tracking 60 bobtails with GPS across South Australia, ecologists at Murdoch University realized the lizards actively avoid their family members.
Bobtails are natural loners, and solitude is relatively easy to find in the sparse desert of southwestern Australia. But analysis showed bobtails have even fewer interactions with their relatives than they do with unrelated lizards.
The results the are the opposite of trends seen among most species. Family ties often bind otherwise indifferent animals, leading to moderate socializing or moments of cooperation — even among shy species.
One recent study showed some birds can recognize distant relatives they’ve never met before, choosing to share food with long lost cousins.
But not bobtails.
“Among males and females, as you might expect, they spent less time together if they were more related to each other, which is a mechanism to avoid inbreeding,” ecologist Stephanie Godfrey told Science Network Western Australia.
“Then among males, and this is probably the finding we were probably more surprised about,” Godfrey continued, “we found that individuals that were unrelated to each other tended to spend more time together.”
Most male-male interactions are based on fighting, so it makes sense that bobtails would avoid getting into a brawl with their relatives.
“They have quite spectacular fights, they’ll grapple onto each other and try to flip each other over — it’s quite a costly exercise if you’re a male lizard because it can lead to debilitating injuries,” Godfrey said.
Interestingly, despite their distaste for familial get-togethers, bobtails are monogamous — forging long-term bonds with a single mate.
“The same pairs will tend to reunite in consecutive years, and there was even, I think, one pair recorded that’s been found in consecutive years for over 20 years,” Godfrey said. “It’s really quite a remarkable system and really unusual in lizards, and even in other species.”