Why Are Our Brains So Big? Scientists Have a Few Possible Answers

iStock
iStock

Human brains are big. They account for about 2 percent of our body mass—a higher percentage than most other species—and they’re triple the size of those belonging to our common ancestor, the ape-like Australopithecines. While there’s no consensus on how and why our brains got to be so big, scientists have suggested a new theory that contradicts earlier ideas.

As phys.org reports, a study published in the journal Nature contains evidence that the human brain evolved in response to ecological stress. Faced with a harsh environment, the brain grew to help humans better survive and provide for their offspring, the scientists believe. Previously, studies suggested that the brain evolved as humans began to engage in more complex social interactions. The researchers behind this new study say their findings suggest otherwise.

“The findings are intriguing because they suggest that some aspects of social complexity are more likely to be consequences rather than causes of our large brain size,” Mauricio González-Forero, the paper’s co-author and a mathematical evolutionary biologist at Scotland’s University of St. Andrews, tells phys.org. “The large human brain is more likely to stem from ecological problem-solving and cumulative culture than it is from social maneuvering.”

They reached this conclusion by using computer software to simulate evolution. Data relating to how much energy an adult human female needs to support the brain was plugged in, as well as energy requirements relative to body size, the Indiana Gazette reports.

Overall, researchers determined through their model that the main challenges that spurred brain growth were overwhelmingly (60 percent) ecological in nature, but it also may have resulted from cooperation (30 percent) and competition between groups (10 percent). Researchers said the ability to acquire new skills is also a crucial component when considering how human brains evolved.

“Ecological challenges can only lead to brain size of this scale if they are coupled with the ability to continue learning from others,” González-Forero said. “The paper is suggesting that human brain development is an interaction between these two things—ecological pressures and culture.”

[h/t phys.org]

11 Lively Gifts for Plant Parents

Blue Q/Amazon/Picnic Time/World Market
Blue Q/Amazon/Picnic Time/World Market

Many folks have been showing off their green thumbs this year thanks to the pandemic, so why not encourage their hobbies? There's a special gift for every kind of plant parent out there—think starter grow kits to gardening tools to cute cartoon socks. If the Christmas tree in the living room isn't enough greenery for your gift recipient's taste this festive season, we have some great gift options below.

1. Back To The Roots Garden In A Can Herb Growing Kit; $25

Back to the Roots/World Market

Herb gardens are compact, useful, and easy to maintain. If your giftee lives in an apartment and doesn't have outdoor space for a large garden, Back To The Roots's Garden In A Can Herb Growing Kit—a three-pack of basil, cilantro, and mint—is a great place for them to start their indoor horticultural journey.

Buy it: World Market

2. Plants Rock Cactus Growing Kit; $13

Plants Rock/World Market

Another option for small spaces is cacti, which do not require much water or attention. This kit makes it easy to start growing cacti in your gift recient's home. The tools are all included, so all your giftee has to do is plant the seeds and set the ceramic pot in a sunny spot.

Buy it: World Market

3. Picnic Time Folding Garden Stool With Tools; $69

Picnic Time/World Market

For more experienced gardeners, tools are essential for helping plants thrive. This stool with tools might solve the problem of sore knees and backs from kneeling in dirt. Not only is the seat portable and lightweight, but it also includes a storage tote and five pockets for tools like the included trowels and garden forks.

Buy it: World Market

4. Green and Pink Ribbed-Glass Plant Misters; $26

World Market

Indoor plants need as much care and attention as their outdoor cousins, but lugging around a watering can may cause a mess in your giftee's home. Using this set of two plant misters is an easy way to keep moisture-loving plants like orchids and Boston ferns nice and dewy.

Buy it: World Market

5. Cotton Macramé Plant Hanger; $18

World Market

Macramé plant hangers were all the rage back in the '70s. They've made a comeback this year as people have become craftier at home. This plant hanger is great for showing off plants that grow long, curtain-like tendrils and helpful when your giftee lives in a small space. With the roof as the limit, they can pack in as many plants as they want.

Buy it: World Market

6. Can't Kill Me 2021 Calendar; $8

TF Publishing/World Market

If your gift recipient loves plants but can't keep real ones alive, give them this mini wall calendar. It features, well, plant arrangements they can't kill, like succulents, bonsai trees, and snake plants. This calendar will surely add a dose of green to their home office.

Buy it: World Market

7. The New Plant Parent: Develop Your Green Thumb and Care for Your House-Plant Family; $17

Harry N. Abrams/Amazon

All gardeners want one simple thing: to know more about keeping their plants alive and thriving. This book has all the essentials for cultivating houseplants. It's full of tips and tricks for repotting a plant, taking care of certain types of plants, and adjusting light for your plant baby's survival.

Buy it: Amazon

8. Homenote Bamboo Plant Labels; $14

HOMENOTE/Amazon

Plant labels are a great way for your giftee to remember where they planted their rosemary versus their parsley before they sprout. This 60 label set comes with a pen, so the labeling process is a breeze.

Buy it: Amazon

9. Blue Q Proud Plant Mom Socks; $13

Blue Q/Amazon

Proud plant moms want to show off their love for their greenery any way they can. That's why these crew socks will be a hit with any of your green-thumbed friends. Blue Q also donates 1 percent of its sales revenue to Doctors Without Borders.

Buy it: Amazon

10. EuroGraphics 1000-Piece Jigsaw Puzzle; $20

EuroGraphics Toys/Amazon

This 1000-piece jigsaw puzzle will occupy your gift recipients from the fall harvest to the spring planting season. The challenging design of multiple succulents features each plant's common and scientific name.

Buy it: Amazon

11. AeroGarden Indoor Hydroponic Garden; $124

AeroGarden/Amazon

If seasons don't matter to your giftee and they want to start their herb garden right now, then the AeroGarden is going to be their best friend. They'll be able to grow herbs like dill, thyme, and mint indoors in the middle of winter. Thanks to the LED grow lights, there is no need to worry about plants getting enough sunlight. They can grow up to six plants at a time, all year round.

Buy it: Amazon

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Late MythBusters Star Grant Imahara Honored With New STEAM Foundation

Grant Imahara attends San Diego Comic-Con
Grant Imahara attends San Diego Comic-Con
Genevieve via Flickr // CC BY 2.0

Fans of MythBusters and White Rabbit Project host Grant Imahara were saddened to hear of his passing due to a brain aneurysm in July 2020 at the age of 49. Imahara, a graduate of the University of Southern California, used the television medium to share his love of science and engineering. Now, his passion for education will continue via an educational foundation developed in his name.

The Grant Imahara STEAM Foundation was announced Thursday, October 23, 2020 by family and friends on what would have been Imahara’s 50th birthday. The Foundation will provide mentorships, grants, and scholarships that will allow students from diverse backgrounds access to STEAM education, which places an emphasis on science, technology, engineering, arts, and math. (Formerly referred to as STEM, the “A” for art was added more recently.)

Imahara had a history of aiding students. While working at Industrial Light and Magic in the early 2000s, he mentored the robotics team at Richmond High School to prepare for the international FIRST Robotics Competition. Whether he was working on television or behind-the-scenes on movies like the Star Wars prequels and The Matrix sequels, Imahara always found time to promote and encourage young engineering talent.

The Grant Imahara STEAM Foundation’s founding board members include Imahara’s mother, Carolyn Imahara, and close friends Don Bies, Anna Bies, Edward Chin, Fon H. Davis, Coya Elliott, and Ioanna Stergiades.

“There are many students, like my son Grant, who need the balance of the technical and the creative, and this is what STEAM is all about,” Carolyn Imahara said in a statement. “I’m so proud of my son’s career, but I’m equally proud of the work he did mentoring students. He would be thrilled that we plan to continue this, plus much more, through The Grant Imahara STEAM Foundation.”

Imahara friend Wade Bick is also launching an effort in concert with the USC Viterbi School of Engineering to name a study lounge after Imahara. Donations can be made here.

You can find out more about the foundation, and make a donation, on its website.