Houston research: Understanding the limit to our professional networks

Houston voices

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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Rice scientist earns $600K NSF award to study distractions in digital age

fresh funding

Rice University psychologist Kirsten Adam has received a $600,000 National Science Foundation CAREER Award to research how visual distractions like phone notifications, flashing alerts, crowded screens and busy workspaces can negatively impact focus—and how the brain works to try to regain it.

The highly competitive five-year NSF grants are given to career faculty members with the potential to serve as academic models and leaders in research and education. Adam’s work will aim to clarify how the brain refocuses in the age of screens, instant gratification and other lingering distractions. The funding will also be used to train graduate students in advanced cognitive neuroscience methods, expand access to electroencephalography (EEG) and for public data sharing.

“Kirsten is a valued member of the School of Social Sciences, and we are thrilled that she has been awarded the prestigious NSF CAREER,” Rachel Kimbro, dean of social sciences, said in a news release. “Because distractions continue to increase all around us, her research is timely and imperative to understanding their widespread impacts on the human brain.”

In Adam’s lab, participants complete simplified visual search tasks while their brain activity is recorded using EEG, allowing researchers to measure attention shifts in real time. This process then captures the moment attention is drawn from a goal and how much effort it takes to refocus.

According to Rice, Adam’s work will test long-standing theories about distraction. The research is meant to have real-world implications for jobs and aspects of everyday life where attention to detail is key, including medical imaging, airport security screening and even driving.

“At any given moment, there’s far more information in the world than our brains can process,” Adam added in the release. “Attention is what determines what reaches our awareness and what doesn’t.”

Additionally, the research could inform the design of new technologies that would support focus and decision-making, according to Rice.

“We’re not trying to make attention limitless,” Adam added. “We’re trying to understand how it actually works, so we can stop designing environments and expectations that fight against it.”

12 Houston climatetech startups join Greentown Labs' growing incubator

Startup Talk

More than 40 climatetech startups joined the Greentown Labs Houston community in the second half of 2025, 12 of which hail from the Bayou City.

The companies are among a group of nearly 70 total that joined the climatetech incubator, which is co-located in Houston and Boston, in Q3 and Q4.

The new companies that have joined the Houston incubator specialize in a variety of clean energy applications, from green hydrogen-producing water-splitting cycles to drones that service wind turbines.

The local startups that joined Greentown Houston include:

  • Houston-based Wise Energie, which delivers turnkey microgrids that blend vertical-axis wind, solar PV, and battery storage into a single, silent system.
  • The Woodlands-based Resollant, which is developing compact, zero-emissions hydrogen and carbon reactors to provide low-cost, scalable clean hydrogen and high-purity carbon for the energy and manufacturing sectors.
  • Houston-based ClarityCastle, which designs and manufactures modular, soundproof work pods that replace traditional drywall construction with reusable, low-waste alternatives made from recycled materials.
  • Houston-based WattSto Energy, which manufactures vanadium redox flow batteries to deliver long-duration storage for both grid-scale projects and off-grid microgrids.
  • Houston-based AMPeers, which delivers advanced, high-temperature superconductors in the U.S. at a fraction of traditional costs.
  • Houston-based Biosimo, which is developing bio-based platform chemicals, pioneering sustainable chemistry for a healthier planet and economy.
  • Houston-based Ententia, which offers purpose-built, generative AI for industry.
  • Houston-based GeoKiln Energy Innovation, which is developing a new way to produce clean hydrogen by accelerating natural geologic reactions in iron-rich rock formations using precision electrical heating.
  • Houston-based Timbergrove, which builds AI and IoT solutions that connect and optimize assets—boosting visibility, safety, and efficiency.
  • Houston-based dataVediK, which combines energy-domain expertise with advanced machine learning and intelligent automation to empower organizations to achieve operational excellence and accelerate their sustainability goals.
  • Houston-based Resonant Thermal Systems, which uses a resonant energy-transfer (RET) system to extract critical minerals from industrial and natural brines without using membranes or grid electricity.
  • Houston-based Torres Orbital Mining (TOM),which develops autonomous excavation systems for extreme environments on Earth and the moon, enabling safe, data-driven resource recovery and laying the groundwork for sustainable off-world industry.

Other startups from around the world joined the Houston incubator in the same time period, including:

More than 100 startups joined Greentown this year, according to an end-of-year reflection shared by Greentown CEO Georgina Campbell Flatter.

Flatter joined Greentown in the top leadership role in February 2025. She succeeded former CEO and president Kevin Knobloch, who stepped down in July 2024.

"I moved back to the United States in March 2025 after six years overseas—2,000 miles, three children, and one very patient husband later. Over these months, I’ve had the chance to hear from the entrepreneurs, industry leaders, investors, and partners who make this community thrive. What I’ve experienced has left me brimming with urgent optimism for the future we’re building together," she said in the release.

According to Flatter, Greentown alumni raised more than $2 billion this year and created more than 3,000 jobs.

"Greentown startups and ecosystem leaders—from Boston, Houston, and beyond—are showing that we can move further and faster together. That we don’t have to choose between more energy or lower emissions, or between increasing sustainability and boosting profit. I call this the power of 'and,'" Flatter added. "We’re working for energy and climate, innovation and scale, legacy industry and startups, prosperity for people and planet. The 'and' is where possibility expands."

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This article originally appeared on EnergyCaptialHTX.com.

Intuitive Machines forms partnership with Italian companies for lunar exploration services

to the moon

Houston-based space technology, infrastructure and services company Intuitive Machines has forged a partnership with two Italian companies to offer infrastructure, communication and navigation services for exploration of the moon.

Intuitive Machines’ agreement with the two companies, Leonardo and Telespazio, paves the way for collaboration on satellite services for NASA, a customer of Intuitive Machines, and the European Space Agency, a customer of Leonardo and Telespazio. Leonardo, an aerospace, defense and security company, is the majority owner of Telespazio, a provider of satellite technology and services.

“Resilient, secure, and scalable space infrastructure and space data networks are vital to customers who want to push farther on the lunar surface and beyond to Mars,” Steve Altemus, co-founder and CEO of Intuitive Machine, said in a news release.

Massimo Claudio Comparini, managing director of Leonardo’s space division, added that the partnership with Intuitive Machines is a big step toward enabling human and robotic missions from the U.S., Europe and other places “to access a robust communications network and high-precision navigation services while operating in the lunar environment.”

Intuitive Machines recently expanded its Houston Spaceport facilities to ramp up in-house production of satellites. The company’s first satellite will launch with its upcoming IM‑3 lunar mission.

Intuitive Machines says it ultimately wants to establish a “center of space excellence” at Houston Spaceport to support missions to the moon, Mars and the region between Earth and the moon.

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