6-month checkup: Dire wolves brought back from extinction are growing fast!

(WJW) — They grow up so fast!

Two dire wolves essentially revived from extinction are reportedly growing, developing and hitting all of their milestones as they’ve recently surpassed the 6-month mark.

Two males, Romulus and Remus, and a younger female pup, Khaleesi, were created from DNA taken from a 13,000-year-old tooth and a 72,000-year-old skull, according to biotech companyColossal Biosciences.

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The company says while extinction is forever, scientistsare trying “the next best thing” and genetically engineering living animals with qualities resembling extinct species. It’s believed the dire wolf had previously been extinct for more than 12,000 years, according to Colossal.

This undated photo provided by Colossal Biosciences shows two pups that were genetically engineered with similarities to the extinct dire wolf. (Colossal Biosciences via AP)

The dire wolves are being raised on an undisclosed nature preserve registered with the U.S. Department of Agriculture.

A recent video shared by the company gives viewers an up-close look at the growing pups and explains their sizes, diets and roles.

HOW BIG ARE THEY NOW?

According to Chief Animal Officer with Colossal Biosciences, Matt James, Romulus and Remus, who are both a little more than 6 months-old, weigh more than 90 pounds, which is about 20% larger than a standard gray wolf.

“We can really tell that the dire wolf genes are kicking in and we’re getting these nice, large wolves that are much more representative of what we saw in the ancient specimens,” James said.

This undated photo provided by Colossal Biosciences shows Romulus and Remus, both 3-months old and genetically engineered with similarities to the extinct dire wolf. (Colossal Biosciences via AP)

Khaleesi, who is a little younger than the two males, weighs about 35 pounds and, according to James, it still tracking about 10-15% larger than gray wolves.

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The video also explains that Romulus and Remus are getting ready for their first vet appointments where their blood will be drawn. Scientists say this will give them a better idea about the animal’s skeletal and muscular systems.

WHO’S IN CHARGE?

Remus now, but that could change.

According to Paige McNickel, who manages the dire wolves’ daily care team, Remus has taken the Alpha role while Romulus’ behavior indicates a beta role.

For example, Romulus will typically go places first while Remus leads from the back. Additional evidence of their roles has been observed when they eat, play and explore new things.

“Remus really likes to watch things and he figures stuff out,”McNickel said. “He’s crafty and he’s always watching.”

McNickel said their roles may change when Khaleesi is added to the mix. Right now, she’s being kept separate from the males.

“As they’re still young that pack dynamic isn’t set. It’s still very fluid,” McNickel said.

WHAT DO THEY EAT?

Though the animals are still young, they’re eating like they’re fully grown adults.

Romulus and Remus are fed high quality dog kibble and ground meat, and sometimes organ meats. They also have access to bones, like rib bones and knuckle bones.

As the wolves continue to grow, they’ll be offered “whole prey items,” which McNickel explained are bigger chucks of meat.

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“And help them develop those abilities and instincts where they would be eating in a group just like they would in the wild. So eating some kind of carcass,” she said.

WHEN WILL KHALEESI JOIN?

While Romulus and Remus are together all the time, Khaleesi is being kept separate until keepers feel it’s safe to integrate her into the pack.

McNickel explained the three wolves will go through a process where they will be able to see and smell each other, but not physically interact. Once keepers are convinced they’re positively interacting, they’ll move Khaleesi in with her brothers.

“We have to kind of let her grow up and catch up with the older brothers,” McNickel said. “And we want to make sure we’ve done all of our steps so it is very safe and a positive experience for all three of them.”

In addition to the dire wolves, Colossal is also also working to bring back the woolly mammoth through gene editing.

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