Fascinating new discovery about breastfeeding dates back to the Ice Age

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For the first time, scientists say they have "evidence of selection on the human maternal-infant bond"—and it has something to do with an incredible connection between breastfeeding and the dental patterns of some population groups during the last ice age.


According to researchers out of the University of California-Berkley, Native Americans and northern Asians who lived some 20,000 years ago were the first to develop uniquely shaped incisor teeth, which are still common only among these populations. The origin of this adaptation stumped biologists until they determined the gene that controls the development of those teeth is the same gene responsible for mammary duct growth.

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As for the reason this trait is just found among Native Americans and northern Asians who lived during the ice age: The researchers believe the women's bodies were adapting to provide more fat and more vitamin D to support their hardy northern babies.

"This highlights the importance of the mother-infant relationship and how essential it has been for human survival," says Leslea Hlusko, an associate professor of integrative biology at the University of California-Berkeley, in a press release.

According to the research published this week in the journal Proceedings of the National Academy of Sciences, the researchers began by looking into the development of the shovel-shaped incisors that were found among nearly 100% of Native Americans before European colonization and remain common in East Asia.

With no obvious reason for the development of the tooth shape, Hlusko says they figured it was packaged with another, more rational evolutionary development. As she says, "When you have shared genetic effects across the body, selection for one trait will result in everything else going along for the ride."

Unsatisfied with the previous hypothesis on the development of those teeth, Hlusko and her co-author launched an investigation by studying the genetics of the population that lived in the high-latitude Beringian refugium during the last ice age, where it was hard to come by natural vitamin D. They found that the gene EDAR was tied to both mammary duct growth and the incisor teeth.

"We know they had a diet that was attempting to compensate for it from the archaeological record, and because there is evidence of selection in this population for specific alleles of the genes that influence fatty acid synthesis," Hlusko says. "It looks like this mutation of the EDAR gene was also selected for in that ancestral population, and EDAR's effects on mammary glands is the most likely target of the selection."

This doesn't mean much for humans living today. But it is amazing proof that women's bodies have been responding in significant ways to the needs of their babies for thousands of years—because we're incredible like that.

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There are few kids television shows as successful as PAW Patrol. The Spin Masters series has spawned countless toys and clothing deals, a live show and now, a movie.

That's right mama, PAW Patrol is coming to the big screen in 2021.

The big-screen version of PAW Patrol will be made with Nickelodeon Movies and will be distributed by Paramount Pictures.

"We are thrilled to partner with Paramount and Nickelodeon to bring the PAW Patrol franchise, and the characters that children love, to the big screen," Spin Master Entertainment's Executive Vice President, Jennifer Dodge, announced Friday.

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"This first foray into the arena of feature film marks a significant strategic expansion for Spin Master Entertainment and our properties. This demonstrates our commitment to harnessing our own internal entertainment production teams to develop and deliver IP in a motion picture format and allows us to connect our characters to fans through shared theatrical experiences," Dodge says.

No word on the plot yet, but we're gonna bet there's a problem, 'round Aventure Bay, and Ryder and his team of pups will come and save the day.

We cannot even imagine how excited little PAW Patrol fans will be when this hits theatres in 2021. It's still too early to buy advance tickets but we would if we could!

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Chrissy Teigen is one of the most famous moms in the world and definitely one of the most famous moms on social media.

She's the Queen of Twitter and at least the Duchess of Instagram but with a massive following comes a massive dose of mom-shame, and Teigen admits the online comments criticizing her parenting affects her.

"It's pretty much everything," Teigen told Today, noting that the bulk of the criticism falls into three categories: How she feeds her kids, how she uses her car seats and screen time.

"Any time I post a picture of them holding ribs or eating sausage, I get a lot of criticism," she explained. "Vegans and vegetarians are mad and feel that we're forcing meat upon them at a young age. They freak out."

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Teigen continues: "If they get a glimpse of the car seat there is a lot of buckle talk. Maybe for one half of a second, the strap slipped down. And TV is another big one. We have TV on a lot in my house. John and I work on television; we love watching television."

Teigen wants the shame to stop, not just for herself but for all the other moms who feel it. (And we agree.)

"Hearing that nine out of 10 moms don't feel like they're doing a good enough job is terrible," she said. "We're all so worried that we're not doing all that we can, when we really are."

The inspiration for Teigen talking publicly about mom-shame may be in part because of her participation in Pampers' "Share the Love" campaign. But even though Teigen's discussion coincides with this campaign, the message remains equally important. Advertising can be a powerful tool for shifting the way society thinks about what's "normal" and we would much rather see companies speaking out against mom-shame than inducing it to sell more stuff.

Calling out mom-shame in our culture is worth doing in our lives, our communities and yes, our diaper commercials. Thank you Chrissy (and thank you, Pampers).

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Gabrielle Union + Dwyane Wade have been blended family goals, an inspiration to those struggling with infertility and now they are an inspiration to parents of trans kids and supporters of trans rights.

Earlier this month Wade appeared on The Ellen DeGeneres Show, and spoke about his 12-year-old daughter Zaya coming out as transgender and Union posted a beautiful video + caption to Instagram, inviting fans to "meet Zaya."

This week Wade appeared on Good Morning America, explaining that Zaya has known she was transgender since she was 3 years old.

"Zaya has known it for nine years," the proud dad said on GMA, adding that he credits Zaya (who was assigned as male at birth) with educating him and helping him grow.

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"I knew early on that I had to check myself... I've been a person in the locker room that has been a part of the conversation that has said the wrong phrases and the wrong words myself," he told GMA's Robin Roberts. "My daughter was my first interaction when it comes to having to deal with this conversation...Hopefully I'm dealing with it the right way... Inside our home we see the smile on my daughter's face, we see the confidence that she's able to walk around and be herself and that's when you know you're doing right."

It sure seems like Wade and Union have been doing it right. When Union posted a video to Instagram earlier this month introducing Zaya it was clear the tween's dad and step-mom have her back.

In the video Zaya is riding in a golf cart with her dad and dropping wisdom. She says: "Just be true to yourself, because what's the point of even living on this earth if you're going to try to be someone you're not?...Be true and don't really care what the 'stereotypical' way of being you is."

Union was so impressed by her step-daughter, captioning the video: "She's compassionate, loving, whip smart and we are so proud of her. It's Ok to listen to, love & respect your children exactly as they are. Love and light good people."

Later in the week Union addressed criticism of Zaya's transition on Twitter, writing: "This has been a journey. We're still humbly learning but we decided quickly w/ our family that we wouldn't be led by fear. We refuse to sacrifice the freedom to live authentically becuz we are afraid of what ppl might say. U have the ability to learn & evolve."

Zaya's big brother is also on her side. Newly 18-year-old Zaire posted the cutest throwback pic from when he and Zaya were just little kids, noting how the siblings were and are best friends.

"Man, I remember bugging my mom as a kid telling her I wanted a brother so bad. I was the only child looking for company and someone to look after and take care of," Zaire began his caption. "I have been blessed to have my best friend, Zaya with me for 12 years. We did everything together … we fought, we played, we laughed and we cried. But the one thing we never did was leave each other behind."

Zaire continued: "I've told you that I would lay my life down to make sure you are ten toes down and happy on this earth," he told his younger sibling. "I don't care what they think Z, you are my best friend and I love you kid, and if it means anything, just know there's no love lost on this side ✊🏾"

We are so impressed and inspired by the love Zaya's family is showing her (and other kids by sharing this story publicly). You've got this Zaya!

[A version of this story was posted February 12, 2020. It has been updated.]

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Back in August the the U.S. Consumer Product Safety Commission (CPSC) and Contigo announced the recall of millions of Contigo Kids Cleanable water bottles—about 5.7 million of them.

Now, the CPSC and Contigo are recalling millions of water bottles and the replacement lids that were given to consumers as part of the August 2019 recall.

"Consumers should immediately stop using the recalled water bottles and the replacement lids provided in the previous recall, take them away from children, and contact Contigo for a free water bottle. Consumers who received replacement lids in the previous recall should contact Contigo for the new water bottle," the CPSC states.

Millions of Contigo Kids Cleanable water bottles were originally recalled after it became clear the silicone spout could pose a choking hazard.

"Contigo identified that the water bottle's clear silicone spout in some cases may detach from the lid of the water bottle," Contigo stated in a notice posted to its Facebook page back in August.

According to the CPSC, "Contigo [had] received 149 reports of the spout detaching including 18 spouts found in children's mouths" before the original recall.

Now, the CPSC reports "Contigo has received a total of 427 reports of the spout detaching including 27 spouts found in children's mouths."

All of the recalled water bottles have a black color spout base and spout cover.

This week Contigo expanded the recall. The original date range was for Contigo Kids Cleanable Water Bottle from April 2018 through June 2019. Now it is for bottles purchased through February 2020, and all the replacement lids.

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If you are looking for some alternative water bottles, here are a few of our favorites:

Hydro Flask

Hydro Flask features an easy-to-drink (and clean) top, a silicone bottom that won't scratch your furniture.

Motherly has tested these with a two-year-old and an eight-year-old and found these bottles are perfect for Pre-K to elementary school.

$29.95

CamelBak

The CamelBak is a big hit with little kids as it is easy to maneuver and it's a big hit with moms because it is easy to clean in the top rack of the dishwasher. CamelBak Eddy 12 oz Kids Vacuum Stainless Water Bottle

$14.99

Skip Hop

The designs on the Skip Hop stainless steel bottle keep kids happy and the silicone sleeve keeps the bottle from falling out of little hands! Bonus points for a flexible straw that is easy to clean!

$17.99


Motherly is your daily #momlife manual; we are here to help you easily find the best, most beautiful products for your life that actually work. We share what we love—and we may receive a commission if you choose to buy. You've got this.

{A version of this story was originally posted August 27, 2019. It has been updated.]

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