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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Houston VC funding surged in 2024, fueled by major Q4 activity

by the numbers

The venture capital haul for Houston-area startups jumped 23 percent from 2023 to 2024, according to the latest PitchBook-NVCA Venture Monitor.

The fundraising total for startups in the region climbed from $1.49 billion in 2023 to $1.83 billion in 2024, PitchBook-NVCA Venture Monitor data shows.

Roughly half of the 2024 sum, $914.3 million, came in the fourth quarter. By comparison, Houston-area startups collected $291.3 million in VC during the fourth quarter of 2023.

Among the Houston-area startups contributing to the impressive VC total in the fourth quarter of 2024 was geothermal energy startup Fervo Energy. PitchBook attributes $634 million in fourth-quarter VC to Fervo, with fulfillment services company Cart.com at $50 million, and chemical manufacturing platform Mstack and superconducting wire manufacturer MetOx International at $40 million each.

Across the country, VC deals total $209 billion in 2024, compared with $162.2 billion in 2023. Nearly half (46 percent) of all VC funding in North America last year went to AI startups, PitchBook says. PitchBook’s lead VC analyst for the U.S., Kyle Stanford, says that AI “continues to be the story of the market.”

PitchBook forecasts a “moderately positive” 2025 for venture capital in the U.S.

“That does not mean that challenges are gone. Flat and down rounds will likely continue at higher paces than the market is accustomed to. More companies will likely shut down or fall out of the venture funding cycle,” says PitchBook. “However, both of those expectations are holdovers from 2021.”

Justice Department sues to block Houston-based HPE's $14B buyout of Juniper

M&A News

The Justice Department sued to block Hewlett Packard Enterprise's $14 billion acquisition of rival Juniper Networks on Thursday, the first attempt to stop a merger by a new Trump administration that is expected to take a softer approach to mergers.

The Justice complaint alleges that Hewlett Packer Enterprise, under increased competitive pressure from the fast-rising Juniper, was forced to discount products and services and invest more in its own innovation, eventually leading the company to simply buy its rival.

The lawsuit said that the combination of businesses would eliminate competition, raise prices and reduce innovation.

HPE and Juniper issued a joint statement Thursday, saying the companies strongly oppose the DOJ's decision.

“We will vigorously defend against the Department of Justice’s overreaching interpretation of antitrust laws and will demonstrate how this transaction will provide customers with greater innovation and choice, positively change the dynamics in the networking market,” the companies said.

The combined company would create more competition, not less, the companies said.

The Justice Department's intervention — the first of the new administration and just 10 days after Donald Trump's inauguration — comes as somewhat of a surprise. Most predicted a second Trump administration to ease up on antitrust enforcement and be more receptive to mergers and deal-making after years of hypervigilance under former President Joe Biden’s watch.

Hewlett Packard Enterprise announced one year ago that it was buying Juniper Networks for $40 a share in a deal expected to double HPE’s networking business.

In its complaint, the government painted a picture of Hewlett Packard Enterprise as a company desperate to keep up with a smaller rival that was taking its business.

HPE salespeople were concerned about the “Juniper threat,” the complaint said, also alleging that one former executive told his team that “there are no rules in a street fight,” encouraging them to “kill” Juniper when competing for sales opportunities.

The Justice Department said that Hewlett Packard Enterprise and Juniper are the U.S.'s second- and third-largest providers of wireless local area network (WLAN) products and services for businesses.

“The proposed transaction between HPE and Juniper, if allowed to proceed, would further consolidate an already highly concentrated market — and leave U.S. enterprises facing two companies commanding over 70% of the market,” the complaint said, adding that Cisco Systems was the industry leader.

Many businesses and investors accused Biden regulatory agencies of antitrust overreach and were looking forward to a friendlier Trump administration.

Under Biden, the Federal Trade Commission sued to block a $24.6 billion merger between Kroger and Albertsons that would have been the largest grocery store merger in U.S. history. Two judges agreed with the FTC’s case, blocking the proposed deal in December.

In 2023, the Department of Justice, through the courts, forced American and JetBlue airlines to abandon their partnership in the northeast U.S., saying it would reduce competition and eventually cost consumers hundreds of millions of dollars a year. That partnership had the blessing of the Trump administration when it took effect in early 2021.

U.S. regulators also proposed last year to break up Google for maintaining an “abusive monopoly” through its market-dominate search engine, Chrome. Court hearings on Google’s punishment are scheduled to begin in April, with the judge aiming to issue a final decision before Labor Day. It’s unclear where the Trump administration stands on the case.

One merger that both Trump and Biden agreed shouldn’t go through is Nippon Steel’s proposed acquisition of U.S. Steel. Biden blocked the nearly $15 billion acquisition just before his term ended. The companies challenged that decision in a federal lawsuit early this year.

Trump has consistently voiced opposition to the deal, questioning why U.S. Steel would sell itself to a foreign company given the regime of new tariffs he has vowed.

Houston space company lands latest NASA deal to advance lunar logistics

To The Moon

Houston-based space exploration, infrastructure, and services company Intuitive Machines has secured about $2.5 million from NASA to study challenges related to carrying cargo on the company’s lunar lander and hauling cargo on the moon. The lander will be used for NASA’s Artemis missions to the moon and eventually to Mars.

“Intuitive Machines has been methodically working on executing lunar delivery, data transmission, and infrastructure service missions, making us uniquely positioned to provide strategies and concepts that may shape lunar logistics and mobility solutions for the Artemis generation,” Intuitive Machines CEO Steve Altemus says in a news release.

“We look forward to bringing our proven expertise together to deliver innovative solutions that establish capabilities on the [moon] and place deeper exploration within reach.”

Intuitive Machines will soon launch its lunar lander on a SpaceX Falcon 9 rocket to deliver NASA technology and science projects, along with commercial payloads, to the moon’s Mons Mouton plateau. Lift-off will happen at NASA’s Kennedy Space Center in Florida within a launch window that starts in late February. It’ll be the lander’s second trip to the moon.

In September, Intuitive Machines landed a deal with NASA that could be worth more than $4.8 billion.

Under the contract, Intuitive Machines will supply communication and navigation services for missions in the “near space” region, which extends from the earth’s surface to beyond the moon.

The five-year deal includes an option to add five years to the contract. The initial round of NASA funding runs through September 2029.