Robin Dunbar, an anthropologist from England, has been studying and refining his theory on how large human networks can realistically get. Graphic by Miguel Tovar/University of Houston

You go to conferences; you network; you collaborate — all researchers and academics do. But do you need more than 150 contacts? Linkedin, Facebook, Twitter — all of these platforms open us up to the possibility of thousands of acquaintances, though fewer we would refer to as "friends."

Studying the primate brain

Robin Dunbar, an anthropologist from England, has been studying and refining his theory of the "Dunbar number" for 30 years. Dunbar became convinced that there was a ratio between brain sizes and group sizes through his studies of primates. "This ratio was mapped out using neuroimaging and observation of time spent on grooming, an important social behavior of primates. Dunbar concluded that the size, relative to the body, of the neocortex – the part of the brain associated with cognition and language – is linked to the size of a cohesive social group," wrote Christine Ro in a 2019 BBC.com Future article.

After the group reached approximately 150, it collapsed.

Your network

Is it true that humans based on their brain, and especially pre-frontal lobe size, are only able to connect in an intimate manner with around 150 other individuals? Defined as someone you would make plans to have a drink or coffee with if you bumped into them randomly on the street, Dunbar's claim is that it seems to be a consistent theme throughout history. Says the BBC: "This rule of 150 remains true for early hunter-gatherer societies as well as a surprising array of modern groupings: offices, communes, factories, residential campsites, military organizations, 11th Century English villages, even Christmas card lists."

The Dunbar number decreases by a "rule of three" where the next step down is the number 50 – those you consider "friends." Then about 15 in a closely knit circle, and four to six only in our familial or closest friend contacts.

Social media and COVID-19

"What determines these layers in real life, in the face-to-face world… is the frequency at which you see people," says Dunbar. "You're having to make a decision every day about how you invest what time you have available for social interaction, and that's limited." So, social media and COVID would seem to be game-changers for this theory.

Dunbar went on to study the process of "grooming" and light touch with astonishing results, which you can read about in the New Yorker. Basically, if a person has a face-to-face encounter with a friend, they are consequently able to withstand unpleasantness right afterwards (their hands stuck into a bucket of ice, for instance!) at a much higher rate.

"It makes sense that there's a finite number of friends most individuals can have," wrote Ro. "What's less clear is whether that capacity is being expanded, or contracted, by the ever-shifting ways people interact online …'It's extremely hard to cry on a virtual shoulder,' Dunbar deadpans."

And how has COVID changed Dunbar's theory? "While our culture has encouraged us to accumulate friends, both on- and offline, like points, the pandemic has laid bare the distinction between quantity and quality of connections," said a New York Times article. "There are those we've longed to see and those it's been a relief not to see."

The Big Idea

Many try to debunk Dunbar's number, by saying that primate and human brains differ and that the calculations are off. Robin Dunbar defends his theory thirty years after first proposing it in The Conversation.

The number of people you can just recognize according to Dunbar, is about 1,500, so you might want to keep that in mind if you are an extrovert and have an incredibly large network of collaborators – both online and offline.

University of Houston's central research department, the Division of Research, has about 100 members. But, your Linkedin network — check the number and see what it sits at. And if it's 600, ask yourself: do you really need that many contacts?

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This article originally appeared on the University of Houston's The Big Idea. Sarah Hill, the author of this piece, is the communications manager for the UH Division of Research.

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12 winners named at CERAWeek clean tech pitch competition in Houston

top teams

Twelve teams from around the country, including several from Houston, took home top honors at this year's Energy Venture Day and Pitch Competition at CERAWeek.

The fast-paced event, held March 25, put on by Rice Alliance, Houston Energy Transition Initiative and TEX-E, invited 36 industry startups and five Texas-based student teams focused on driving efficiency and advancements in the energy transition to present 3.5-minute pitches before investors and industry partners during CERAWeek's Agora program.

The competition is a qualifying event for the Startup World Cup, where teams compete for a $1 million investment prize.

PolyJoule won in the Track C competition and was named the overall winner of the pitch event. The Boston-based company will go on to compete in the Startup World Cup held this fall in San Francisco.

PolyJoule was spun out of MIT and is developing conductive polymer battery technology for energy storage.

Rice University's Resonant Thermal Systems won the second-place prize and $15,000 in the student track, known as TEX-E. The team's STREED solution converts high-salinity water into fresh water while recovering valuable minerals.

Teams from the University of Texas won first and second place in the TEX-E competition, bringing home $25,000 and $10,000, respectively. The student winners were:

Companies that pitched in the three industry tracts competed for non-monetary awards. Here are the companies named "most-promising" by the judges:

Track A | Industrial Efficiency & Decarbonization

Track B | Advanced Manufacturing, Materials, & Other Advanced Technologies

  • First: Licube, based in Houston
  • Second: ZettaJoule, based in Houston and Maryland
  • Third: Oleo

Track C | Innovations for Traditional Energy, Electricity, & the Grid

The teams at this year's Energy Venture Day have collectively raised $707 million in funding, according to Rice. They represent six countries and 12 states. See the full list of companies and investor groups that participated here.

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This article originally appeared on our sister site, EnergyCapitalHTX.com.

Houston startup is off to the races with its innovative running shoes

running start

Despite Houston’s reputation as a sneaker town, there are few actual shoe companies headquartered in the Bayou City. One that is up and running is Veloci Running, an innovative enterprise that combines the founder’s history as a track runner for Rice University with the realities of running in a changing world.

Tyler Strothman started running cross country growing up in Wisconsin and Indiana before moving to Texas to attend Rice in 2020. Naturally, his college life was altered significantly by the COVID-19 pandemic. Unfortunately, Strothman contracted the virus, leading to pneumonia and causing him to consider other plans for his future.

One thing that stood out from Strothman’s running career was how bad his shoes fit.

“Traditional shoes narrowed in, cramped the front of my feet, and it was causing foot pain,” he said in a video interview. “But any other shoes that were shaped to better fit the natural foot shape were more barefoot (style)—they were more minimalist overall. And that was hurting my calf and Achilles. It was pulling on it, kind of like a rubber band.”

Strothman decided to start Veloci and went on to win the annual Liu Idea Lab for Innovation and Entrepreneurship's H. Albert Napier Rice Launch Challenge in 2025. The win secured $50,000 in startup money, which Strothman used to immediately launch his new runner-centered shoe design with himself as the CEO at the age of 24.

Along for the jog was Strothman’s college friend, Austin Escamilla, who serves as chief operating officer. Escamilla believed in Strothman’s vision, but the project immediately ran into snags beyond Veloci’s control, particularly with manufacturing in Asia.

“It was quite a year to start a shoe business, especially dealing with tariffs and global economic trade tensions,” he said in the same video interview. “We've luckily had some really good partners and really solid advisors throughout the journey who've either done it or had some good feedback and advice. It certainly takes a village, but every day is different. So, it's fun to come into work every day and problem solve.”

The flagship Veloci shoe is the Ascent, which comes in both men’s and women’s sizes. It combines the wide toe cage that Strothman wanted with extra support cushion for a softer, easier run. They retail at $180. Strothman has personally been testing them for a year, noticing reduced lower leg pain when he runs.

At the same time, Veloci has attended to some of the more unique running problems in Houston and other hot, Southern states. A combination of heat and humidity makes for a very soggy shoe if not designed with such environments in mind. The Ascent is built to be very open and breathable, allowing hot air to flow and keeping sweat from building up. These various comfort improvements have made the Ascent Strothman’s favorite running shoe.

“I put on more pairs of this Veloci shoe than I have in my other running shoes in the last seven years,” he said

Currently, Veloci is still a very niche brand. Since the company launched last year, they’ve sold roughly 10,000 pairs. Those sales come either directly through their website or from specialty running stores, most of which are located around the Houston area, like Clear Creek Running Company in League City.

Building community around the shoe through these specialty retailers has been a prime marketing strategy. Part of the $50,000 grant went to a custom van that Veloci can take to various 5Ks, runs and events to get people interested in the brand. The personal touch has helped news of Veloci spread through the running world.

“We went to many run clubs throughout the last year,” said Escamillia. “We've been to pretty much every one of the major run clubs at least once or twice. Folks who try on the shoes, love them, become fans and post and repost…. The marketing side's been a lot of fun.”

Intuitive Machines lands $180M NASA contract for lunar delivery mission

to the moon

NASA has awarded Intuitive Machines a $180.4 million Commercial Lunar Payload Services (CLPS) award to deliver science and technology to the moon.

This is the fifth CLPS award the Houston spacetech company has received from NASA, according to a release. It will be the first mission to utilize Intuitive Machines' larger cargo lunar lander, Nova-D.

Known as IM-5, the mission is expected to deliver seven payloads to Mons Malapert, a ridge near the Lunar South Pole, which is a "compelling location for future communications, navigation, and surface infrastructure," according to the release.

“We believe our space infrastructure provides the scalability and flexibility needed to support an increased cadence of new Artemis missions and advance national objectives. This CLPS award accelerates our expansion efforts as we build, connect, and operate the systems powering that infrastructure,” Steve Altemus, CEO of Intuitive Machines, said in the release. “We look forward to working closely with NASA to deliver mission success on IM-5 and to provide sustained operations and persistent connectivity in the cislunar environment and across the solar system.”

The delivery will include the Australian Space Agency’s lunar rover, known as Roo-ver, and another lunar rover from Honeybee Robotics, a part of Jeff Bezos' Blue Origin. Intuitive Machines will also deliver chemical analysis instruments, radiation detectors and other technologies, as well as a capsule named Sanctuary that shows examples of human achievements.

Intuitive Machines previously completed its IM-1 and IM-2 missions, which put the first commercial lunar lander on the moon and achieved the southernmost lunar landing, respectively.

Its IM-3 mission is expected to deliver international payloads to the moon's Reiner Gamma this year. It’s IM-4 mission, funded by a $116.9 million CLPS award, is expected to deliver six science and technology payloads to the Moon’s South Pole in 2027.

The company also announced a $175 million equity investment to fuel growth earlier this month.