Foursquare CEO Jeff Glueck has explored much of the world, both in a professional capacity and for his own personal enjoyment. The list of cities he's visited and worked in is longer than most, which would make sense for the head of a company that thrives on its users' thirst to explore, discover, and share their own adventures.

From working on economic reform in South America to creating Travelocity's famous traveling gnome ad campaign, Glueck says that his personal and professional experience has helped him pinpoint what he calls the "magic" of Foursquare. 

While at lunch with Business Insider atLure Fish Bar in Manhattan's Soho neighborhood, Glueck shared what he's learned from his journeys through Peru, the former Soviet Union, and Washington, DC, as well as the latest on what's happening at Foursquare.

SEE ALSO: Meet the man behind the on-demand helicopter startup that the 1% use to get to the Hamptons

Glueck chose Lure Fish Bar in Soho for our lunch. Only one block away from Foursquare's headquarters, it's a company favorite.

Glueck discovered Lure the way many people hear about restaurants — from a friend. "[Foursquare founder Dennis] Crowley has [always] loved this place, and Steven Rosenblatt, who's our president, is a regular here as well," Glueck said. "He knows the maître d',
and she greets him, 'Hey Steven, welcome back!'"

"There's both a New York tech element to Lure, and it's a neighborhood spot. It's sort of like 'Cheers' — they know your name," Glueck said. He's an especially big fan of the restaurant's homemade salt and vinegar potato chips, which appeared on the table as we settled in.

Originally hired as Foursquare's COO in 2014, Glueck replaced founder Dennis Crowley as CEO in January. Crowley became the company's executive chairman. 

Around the same time that Glueck became CEO, the company raised a new $45 million financing round led by Union Square Ventures with the participation of past investors like Andreessen Horowitz, but it reportedly had to take a cut in its valuation to do so. 

When Crowley founded Foursquare in 2009, the idea was that people would use the app to virtually "check in" to particular locations. In 2014, it launched a second app, called Swarm, which uses Foursquare's original check-in idea to offer users monetary and virtual prizes for creating a log of where they go. The original Foursquare app — Foursquare City Guide — is now focused on making activity recommendations, similar to Yelp.

With more than 50 million users, Foursquare's apps have now surpassed 10 billion check-ins. In the past two years it has also launched its for-business enterprises, which include selling location data to mobile advertisers and app makers like Uber, Samsung, and most recently, Snapchat.  

At lunch, Glueck was sure to check in on Swarm. Logging his every move is clearly a habit for him. "I particularly like to compete with Fred Wilson [on Swarm]," said Glueck. Wilson, a venture capitalist at Union Square Ventures and an investor in Foursquare, is an avid Swarm user, and he checks in every morning with a photo of his latte. "If I can beat Fred, then I feel like I've had a good week," joked Glueck.

By checking in, Glueck was contributing to the ever-growing data set that Foursquare has about Lure: the restaurant's shape, its popular hours, and how many people have visited it. In fact, it's the Swarm data that has been the cornerstone to Foursquare's enterprise efforts.

Glueck's marketing background helped him see how Swarm's life-logging could be helpful to online advertisers, particularly Foursquare's attribution feature, which can measure how effective digital ad campaigns are at driving people into stores. 

But brick-and-mortar stores aren't the only companies benefitting from seven years' worth of Foursquare check-ins. The "Places" data is also used by Apple, Uber, Twitter, Microsoft, Samsung, and thousands of other developers whose services depend on location information.

It has also been able to use that data to tell other stories — to show that foot traffic at Trump-branded properties decreased during the 2016 presidential campaign, for example, and to help shoppers figure out the best time to hit the mall during the holidays.

Glueck orders the chicken club sandwich, mostly because "the French fries here are fantastic," he says.

Glueck often uses Foursquare's City Guide to help him find local favorites, which, he admits, he used to rely on Yelp for. However, he claims that Foursquare's community has helped him find much better hidden treasures. 

"Because there's such a passionate community of explorers on Foursquare, we find those off-the-beaten-path, special, original places that aren't always the mass market, or the most popular," he said. "And that's the kind of thing I love exploring."

Foursquare users can add "tastes" to their profile to help inform the app's recommendations. Tastes can range from specific favorite foods, like fish tacos and pancakes, to restaurant features, like outdoor seating and karaoke. 

Being in close proximity to the President-elect has its perks, and it appears some real estate agents are looking to take advantage of that.

At least one condominium in Trump Tower — a one-bedroom unit located on the 31st floor and asking $2.1 million — is being advertised as "the best value in the most secure building in Manhattan."

According to Politico, an email blast trumpeting the building's heightened security went out on November 13, the day the unit was listed and only five days after Election Day.

"The New Aminity [sic] – The United States Secret Service," the email read.

The 263 condominiums in Trump Tower are all privately owned. The Trump Organization does manage the building, as well as all the amenities downstairs, and it takes a $2,000 processing fee for unit sales plus $250 per additional adult, Politico says.

The area around Trump Tower has been fortified since Trump was elected, with a heavy police presence and close monitoring of people going into and out of the tower. It is difficult for an average citizen with no legitimate business to get close to — or inside — the tower, which is designated a privately owned public space. Local ground-level tenants around the building have even complained of poor sales in the wake of the election.

It's easy to see why buyers seeking privacy or security might be attracted to the building in light of this. 

The fortification is unlikely to abate soon, as Melania Trump and her 10-year-old son, Barron, have reportedly elected to stay in New York and not move to Washington, DC when her husband takes office. New York City Mayor Bill de Blasio has asked the federal government to reimburse the cost of securing Trump Tower until Inauguration Day, to the tune of $35 million at a rate of $500,000 per day.

A spokesperson for Douglas Elliman Real Estate — whose brokers Ariel Sassoon and Devin Hugh Leahy are listing the unit — did not immediately respond to a request for comment.

SEE ALSO: Trump Tower is actually 10 floors shorter than Donald Trump says it is

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NOW WATCH: The Mayor of NYC is asking congress for $35 million to protect Trump until the inauguration

A startup that's developing an anti-aging supplement just raised $20 million to keep studying it and other supplements. 

Elysium Health, the brainchild of former Sequoia partner Eric Marcotulli, former JPMorgan vice president Dan Alminana, and MIT biology professor Leonard Guarente, raised $20 million from investors including General Catalyst, which also recently led a funding round for cancer genetics startup Color Genomics. 

Supplements are a multi-billion industry that can often be tricky for consumers to navigate. Since most supplements are not designed to treat a specific disease or ailment, they typically aren't regulated in the same way as pharmaceutical drugs. It's not too surprising, then, that many supplements currently on the market do not contain what they say they do. Plus, the science on the alleged benefits of many vitamins and supplements can be mixed. 

This is where Elysium hopes to come in. On Tuesday, the company presented the results from its first randomized controlled clinical trial of its supplements. Those results are intended to show that the supplement is safe and that it appeared to help raise levels of a specific protein in the blood of people who took it.

Also, the company recently added three notable members to its scientific advisory board. These people include the Harvard geneticist George Church, the chairman of dermatology at Weill Cornell Medical College Dr. Richard Granstein, and Nobel Prize-winning biochemist Paul Modrich.

How it works

Elysium's first product is called Basis. It aims to boost the levels of a specific protein called "nicotinamide adenine dinucleotide" (NAD), found in cells. Some studies in mice and yeast suggest that boosting NAD levels may help prevent aging-related decay in important structures in our cells called mitochondria. 

Basis costs about $50 per month if you choose to pay as you go, while a one-time bottle will set you back $60. You can also subscribe for a half or full year, which costs $45 or $40 per month, respectively.

"NAD governs communication between the nucleus and everything else in the cell, as well as how the cells communicate with one another," Marcotulli told Business Insider in April. As we age and NAD levels fall, "the ability to communicate appropriately also drops." In other words, it's like being on the end of a choppy phone line; the less you can hear, the more likely something will get lost in translation and go awry.

Guarente and his research team ultimately decided on two naturally occurring compounds. The first was pterostilbene, a type of micronutrient called a polyphenol that's present in tiny amounts in almonds, grape leaves, and blueberries. The second was nicotinamideriboside, a form of vitamin B3 that's also found in trace amounts in yeast-containing foods and milk-derived products like cheese and yogurt. Both compounds are available separately as supplements.

Elysium hopes that by combining these compounds and providing them in larger quantities than the trace amounts found in food, they could help the body make NAD. 

The first trial

Some research on pterostilibene and nicotinamide riboside showed that the compounds were bioavailable (or able to be absorbed by the body), safe and had some potential anti-aging qualities (at least in rats). 

So the first step was to run a study to make sure that if you did take the Basis supplement, it would increase the amount of NAD relative to those taking the placebo. To test that out, as well as the safety of basis, Elysium looked at 120 participants aged 60-80 over the course of eight weeks. 

For those taking the regular dose (two Basis pills a day), NAD increased by an average of 40% by week 4. In those who took double the dose, it went up 90%. Guarante told Business Insider that in the placebo group, there was no change to NAD. On the safety side, he said, there were very minor side effects, even in the placebo group. 

Notably, Guarante said, the levels of NAD were sustained throughout the trial, instead of temporarily increasing before coming back down even though the participants were still taking the pill.

Next, the company plans to submit the results to a peer-reviewed journal. And now that it's shown that NAD levels seem to increase with the supplement, Elysium will need to also show that those increased levels are tied to anti-aging health outcomes. Those results, Guarante said, should be taking place over the next two years. 

Elysium launched Basis in February 2015, and plans to investigate others focused on improved overall health and wellness.

"The concept of the company is that there are a lot of natural products out there," Guarante told Business Insider in April. "We want to be able to recognize when there's something that's discovered in medical research that has the potential for benefiting human health, and make that available as quickly as possible in a way that's safe."

SEE ALSO: Drug spending around the world will hit $1.5 trillion by 2021

CHECK OUT: A startup that's developing tests that run on a drop of blood just raised $36 million

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NOW WATCH: A dermatologist explains what causes acne and how you can prevent it

For busy, successful people, sleep is a precious commodity, rare and treasured.

So when it comes to getting a solid night of shut-eye, some do everything they can to not let insomnia, pressure at work, or snoring spouses get in the way, even if that means creating a weird nightly routine or napping to get through the day.

But for others — including President-elect Donald Trump — sleep isn't a priority, and they function on just a few hours a night. 

Here's a look at the most bizarre sleeping habits of 13 highly successful people.

This is an update of an article originally written by Vivian Giang.

SEE ALSO: Former Wall Street executive Sallie Krawcheck explains why Trump becoming president 'may be one of the best things that's ever happened for feminists'

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President-elect Donald Trump only sleeps 3 to 4 hours per night.

On a typical night, President-elect Donald Trump only sleeps three to four hours— and sometimes as little as 90 minutes. 

First thing after waking up — typically between 6 and 6:30 a.m. — Trump is then handed a stack of all the newspaper clippings about him, which serve to both keep him informed and boost his ego. According to Michael D'Antonio, author of "Never Enough: Donald Trump and the Pursuit of Success," most of the time, he doesn't even read the clips — he just looks at his name on the pages. 

D'Antonio says that Trump's strange morning habit "gets him going and keeps him sustained" throughout the day. 

Michael Phelps sleeps in a chamber with air comparable to that at an elevation of 8,500 to 9,000 feet.

By engineering his bedroom environment to replicate that of a high altitude, Phelps decreases the amount of oxygen available, which forces his body to work harder to produce more red blood cells and deliver oxygen to his muscles. It also helps Phelps increase his performance endurance and prepare himself for competitions at high elevations.

"Once I'm already in my room I still have to open a door to get into my bed," Phelps said on the CBS News program "60 Minutes" in 2012. "It's just like a giant box. It's like 'boy and the bubble.'"

Arianna Huffington turned her bedroom into a 'slumber palace.'

After collapsing from exhaustion in 2007 — and waking up in a pool of her own blood — Arianna Huffington became an advocate for getting a good night's sleep.

Huffington turned her bedroom into a "slumber palace," complete with a canopied bed and blackout curtains. Before bed, she turns off her phone and plugs all her electronics in to charge overnight — outside the bedroom, according to The Cut. She then takes a hot bath, filled with Epsom salt and lavender oil, to calm her mind and help her forget the stresses of the day. 

What she wears matters as well, and Huffington sleeps only in garments meant for slumber; no old gym T-shirts allowed here. Finally, she dives into a book on poetry or philosophy and lets it lull her to sleep. 

On November 5, 2015 we interviewed Tony Robbins, bestselling author of "Money: Master The Game," reveals the best way to make a good first impression.

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If you want to understand the world, look at how people live. Toys are a good place to start.

Dollar Street, a soon-to-launch project from the Gapminder Foundation, went into hundreds of homes at different income levels around the world to photograph people’s possessions. It makes clear a few things:

—Some people have very, very little.

—People at similar income levels lead similar lives, a sign that economics matter more than culture.

—People at all income levels have a lot number of similarities too. Among them: toys.

"It's striking to see how similar our lives are," Gapminder co-founder Anna Rosling Rönnlund told Business Insider. "It makes the world less scary to see that most people struggle with everyday business most of the time and they are not so exotic and it's not so scary."

With Dollar Street's official launch coming soon, check out some favorite toys around the world.

In an Indian home living on $29/month per adult, the favorite toy is a plastic bottle.

In a Burundian home living on $29/month per adult, the favorite toy is dried maize.

In a Zimbabwean home living on $34/month per adult, the favorite toy is a home-made ball.

Renters and buyers across Manhattan are revolting against rising prices.

Bloomberg's Oshrat Carmiel reported on Tuesday that 432 Park Ave., the slim skyscraper that's the tallest residential building in the world, has sold units this year for an average of 10% less than the original listing price.

The top-floor penthouse overlooking Central Park closed for $87.7 million, 8% less than the listing price, Bloomberg reported.

There are too many luxury buildings in New York, and more are being constructed, which has meant high-end buyers and renters have more options and bargaining power. Meanwhile, owners have to offer more concessions to fend off their competition.

"New York City's rental market has been mostly steady, except at the high end, where the inventory has risen and rents have drifted down," the Federal Reserve said in its most recent Beige Book, based on comments from its contacts in New York.

The Fed added that landlord concessions, from price cuts to free rent, were "increasingly prevalent" in Manhattan and Brooklyn.

Jonathan Miller, president of the appraiser Miller Samuel, told Bloomberg that the 432 Park Ave. developer is likely covering for buyers' taxes because sales prices usually end in odd, unrounded numbers, suggesting subtractions were made.

Head to Bloomberg for the full story »

SEE ALSO: The Fed confirmed some of the most troubling trends in Manhattan real estate

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NOW WATCH: A 58-story luxury apartment in San Francisco is sinking and people aren't sure why

Business Insider released its annual list of the best colleges in America, emphasizing schools with high graduation rates and early-career earnings, rather than focusing solely on glamour statistics, like reputation and selectivity.

But that's not to say that the caliber of the students doesn't play an important role in what makes a school great. So we expanded our ranking to the top-100 schools in the country and filtered our data, the most recent available from the Department of Education, to find which colleges boast students with the highest average SAT scores. For schools that traditionally accept the ACT, those scores have been translated to the equivalent SAT score. 

With an average score of 1534, CalTech topped the list, jumping 40 spots from its ranking on the main list. University of Chicago and MIT followed, moving up 21 and 3 spots, respectively, from their positions on the original ranking. Read on to see the full list of the schools with the highest SAT scores in the US. 

SEE ALSO: The 50 best colleges in America

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22. Brown University

Location: Providence, Rhode Island

Average SAT score: 1425

Brown students have the freedom to personalize their liberal-arts course study, a practice the school calls "open curriculum." Brown was founded in 1764 on the then-unprecedented idea of accepting students regardless of religion. It was also the first Ivy League school to establish an undergraduate engineering program in 1847.

21. Tufts University

Location: Medford, Massachusetts

Average SAT score: 1428

Tufts University is made up of three undergraduate schools: the School of Arts and Sciences, the School of Engineering, and the School of the Museum of Fine Arts at Tufts. Students have the option to choose from about 150 majors and minors and participate in one or more of Tuft's 341 student organizations. In the Experimental College, students go beyond the typical classroom environment, taking courses such as "Circus and Society" or "American Witches."

20. Carnegie Mellon University

Location: Pittsburgh 

Average SAT score: 1432

Located in the heart of Pittsburgh, Carnegie Mellon University carries on the traditions of Scottish founder and steel magnate Andrew Carnegie. Besides academic excellence, that also includes Pipes and Drums, a bagpipe-only band, and Kiltie Band, a quirky marching band that dons kilts for every performance. The school is also known for its top-notch engineering program, and offers majors in everything from chemical engineering to engineering and public policy.  

It's really hard to make the bed every day. Sometimes you're running late, and other times you just don't feel like it. Smartduvet — a device that claims to make the bed for you — is currently available to back on Kickstarter. Here's how it takes all the work out of making the bed.

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As Hollywood is in the midst of another award season — when studios and publicists are hard at work touting the best movies of the year — deep in the bowels of the review aggregator Metacritic, you can find something different: the movies with the dishonor of getting the worst reviews of the year.

From blockbuster duds like "Independence Day: Resurgence" and "Warcraft" to indie misses like "Man Down" and "The Sea of Trees," plus the epically bad A-list romantic comedy "Mother's Day," there are some movies this year that the critics really, really didn’t like.

Here are the 25 worst-reviewed movies of 2016, as rated by critics' scores on Metacritic:

Note: Movies here are limited to those that had a theatrical release.

SEE ALSO: The 50 best TV show seasons of all time, according to critics

25. "Alice Through the Looking Glass"

Metacritic score: 34/100

What a critic said: "I removed my eyeballs from my head as soon as I got back from 'Alice Through the Looking Glass' and cleaned them in a sink." — RogerEbert.com

24. "Ice Age: Collision Course"

Metacritic score: 34/100

What a critic said: "It's time to put this franchise on ice for good." — Time Out London

23. "Zoolander 2"

Metacritic score: 34/100

What a critic said:"The first film scored a few palpable hits, but the new one barely makes the effort." — The New Yorker

Have you heard of the trendy beverage called kombucha? You may have seen it in your local grocery store claiming that it's a miracle drink. Before you add it to your diet, here are a few things you should know.

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NOW WATCH: Here's how the White House master bedroom has changed from president to president

In March 2012, Kristin Addis quit her job as an investment banker in Southern California.

"It was hard for me when our paid time off was only 14 days per year," she tells Business Insider.

"We'd go to the office puking our guts out because we didn't want to use our vacation time being sick. I felt back then like even if I wanted to, in that 14 days, I wasn't really allowed to take it all at once. I felt like 'What is this money worth if I don't have the opportunity to spend it on what I want?

"I thought there had to be more to life than that."

So she set out to find it.

Less than a year later, Addis bought a one-way ticket to Bangkok, planning to travel overland through Southeast Asia. Since then, the now 30-year-old has largely stayed on the move, documenting her journey through her blog, Be My Travel Muse, and sharing the expertise she's gathered in her book, "Conquering Mountains: The Guide to Solo Female Travel," produced with Nomadic Matt's Matt Kepnes.

Below, she talks about the new life she built traveling the world: what it looks like, the reality of working on the road, and how she affords it.

SEE ALSO: 16 people who are living the dream without spending a fortune

Addis, who had lived in Taiwan when she was 21 to study Mandarin, started her trip in Southeast Asia because she'd read a traveler could get by on $1,000 a month, a sharp drop from the $3,000-$4,000 a month price of her California life.

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 In Newport Beach, California.

"I had been saving for years," Addis remembers. "It was between putting money into buying a condo or traveling." She managed to accumulate around $20,000 in cash, plus about $60,000 in retirement funds, which she says she won't touch until it's time to retire.

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At Hohenzollern Castle, Germany.

"I've never had debt other than school debt," Addis says. "I won't spend money I don't have, and I don't want to dip into funds meant for later. If I couldn't make being a travel influencer work, I would have gotten a job before I touched my retirement savings."

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 In Maui, Hawaii.

NYU Otologist Erich Voigt explains the proper way to clean wax out of your ears. Many people think Q-tips can help keep ears clean, but this isn't the case. Learn how Q-tips are making things worse and how you should actually be cleaning your ears.

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In 2014, Dan Zigmond, director of analytics at Facebook, lost more than 20 pounds in less than a year. He didn't track steps or count calories. Instead, Zigmond gave up eating for 15 hours a day.

"I don't think about it as 'fasting,' per se. There's a period of time where I eat, and there's a period of time when I don't," Zigmond told Business Insider. "Life is all about balance."

Zigmond, a father and a practicing Buddhist, subscribes to a trending diet called intermittent fasting, which involves going without food for anywhere from 14 hours to several days.

The science behind intermittent fasting is spotty. Most studies use rodents and fruit flies as test subjects, rather than primates and people, as Scientific American reports. Still, it's catching on among startup workers looking for simple solutions to slim down and sharpen their minds.

A paper from the Salk Institute for Biological Studies turned Zigmond onto intermittent fasting. It suggested that when you eat might matter as much as what you eat. Mice with feedings restricted to certain hours of the day became thinner than mice who were fed whenever, according to the study. Zigmond was reminded of his time living in a Buddhist temple in Thailand, where the monks followed a similar routine, and decided to give it a go.

Zigmond — who counts Microsoft, Google, and YouTube among his past employers — eats during a nine-hour window each day.

Most days begin the same. He wakes around 6 a.m. and takes a quick run around the neighborhood while listening to Kanye West. After getting his kids ready for school and guzzling a large cup of green tea, he arrives at Facebook's Menlo Park, California, campus.

His first meal comes at 9 a.m. Zigmond grabs a bowl of oatmeal topped with Greek yogurt from Facebook's cafeteria, and he sometimes adds a handful of granola, blueberries, or bananas.

"I try to take half an hour for breakfast, without doing any work," Zigmond said.

Through a morning of meetings and writing at his desk, Zigmond tries to stay hydrated by drinking an unsweetened iced tea. When lunch rolls around at noon, he leaves his desk for a full hour and finds a lunch-buddy with whom he can talk about "non-work" stuff.

"I'm very flexible about what I eat at lunch — there's no rules at all," Zigmond said. "Yesterday I had pizza. My favorite is Indian food, but I have to bike over to the other campus for that, so only do that maybe once a week."

In the afternoon, he conducts one-on-one meetings with members of his team, preferably outside. Zigmond walks over 15,000 steps, about seven miles, on a typical work day.

A ginger shot from a nearby juice bar gives him a 3 p.m. boost.

At 5:30, Zigmond gets dinner from the company's extensive cafeteria. Dinner tends to be his smallest meal, since he eats so heartily at lunchtime.

"Often I'll just make a sandwich, which is what I did yesterday. Other times I'll grab a bowl of rice and curry from the cafeteria," he said.

He leaves the office around 7 p.m. to run errands or pick up his daughter from dance. A cup of herbal tea tops off the day. ("I drink a lot of tea.") Lights out at 10 p.m.

Zigmond, who co-authored a book, "Buddha's Diet: The Ancient Art of Losing Weight Without Losing Your Mind," has no plans to change his diet — or lack thereof — anytime soon.

SEE ALSO: These Silicon Valley 'biohackers' are fasting their way to longer, better lives

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I remember the days of coming home from school and tuning into MTV's "TRL," a program that counted down the top music videos in front of screaming mobs of adolescent girls.

Today, teens are finding the same guilty pleasure in an app.

Musical.ly is a video network app, where users — or "musers," as they're called — create 15-second videos of themselves lip-syncing and dancing along to popular music. You can "heart" videos and create digital duets with your "BFFs," or people you follow and who follow you back.

More than 150 million people, mostly teens, have registered. If the demographic isn't abundantly clear from scrolling through the featured videos, the app also reminds you of its target user during sign-up, when it enters 2000 as the default birth year.

After talking with a handful of middle schoolers for Musical.ly tips, I entered the mysterious world of teen-tech to see what the buzz is all about. Here are the basics.

SEE ALSO: How a failed education startup turned into Musical.ly, the most popular app you've probably never heard of

When you open the Musical.ly app, it defaults to a feed of featured videos.

These are often the coolest, most liked videos of the day. The Featured feed is also a good place to find inspiration.

Users, or "musers," include the hashtag #featureme in their posts in order to be discovered by the app's curators.

You can switch to the Follow tab, which shows you videos from the musers you follow.

A majority of teens I talked to said they prefer the Follow tab to Feature. That way, they can easily see what content comes from their friends, as opposed to randoms on the internet.

Being 10 years older than most musers, I don't have many friends on the app. I followed mainstream celebrities like Selena Gomez, Jason Derulo, and Ariana Grande.

Here's what a typical Musical.ly video looks like.

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Identical twins Lisa and Lena, from Germany, have racked up more than 13.7 million followers on Musical.ly and run one of the fastest growing Instagram accounts.

The teens joined Musical.ly a year ago, and their videos have since soared in production quality, thanks to lighting, choreography, and matching outfits from their own clothing line.

Ah, the office holiday party. A sticky social situation to navigate. 

The holiday party is often seen by some to be the perfect opportunity to ruin their carefully cultivated work reputation by drinking one too many gin and tonics and taking over the dance floor when Mariah Carey's "All I Want for Christmas Is You" suddenly blares over the rented restaurant's speakers.

That kind of embarrassment will be difficult to avoid, unfortunately. What's easier to avoid: looking like a fool in your outfit.

Dressing for the annual holiday party is tricky. It's not a work setting — there's no need to dress like you do for work. In fact, if you do, your colleagues might label you a square addicted to your job, or worse: a Grinch.

Dress too far outside of the norm, and you may create an altogether different impression on many people who haven't seen you outside of the 8th-floor conference room before, however. (Read: Leave the Phish band T-shirts at home.)

So what can you do? First, identify the dress code of the party. This isn't always easy, as it will more than likely not be stated plainly on the invite. In such a case, employ the "office dress code minus one" rule. If your office dress code is business professional, dress business casual for the party. If your workmates dress closer to business casual on any given work day, don't be afraid to wear jeans and ditch the tie.

Second, remember that it's a holiday party. That means don't be boring. Sure, you can wear a grim charcoal business suit, but then you shouldn't be surprised when a stranger offers their condolences.

Liven it up a little. A statement piece — like a candy cane pin on your blazer or a pair of patterned menorah socks— are just the ticket.

As for not making a fool of yourself when you actually get to the party: you're on your own.

SEE ALSO: 7 rules for flying like a modern gentleman

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As both a sports and concert photographer, Michael Zagaris might be a bit of an adrenaline junkie.

"When you come on to the field, you feel not only the eyes of the people; you feel the energy in every molecule of the body ... The same with a rock and roll show," he recently told Business Insider.

In his new book, "Total Excess," Zagaris holds nothing back, sharing all of the gritty details of what life was like for bands like The Rolling Stones, Led Zeppelin, and The Who in the '70s, when they were at the top of the world of rock 'n' roll.

The photos are also appearing in a gallery show at Milk Gallery through December 18. They show a previously unseen behind-the-scenes look at what it's like to be a rock star, from both the front of the stage and behind it.

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Zagaris first photographed The Rolling Stones in 1972. After several failed attempts at getting a photo pass to their shows, Zagaris landed the job by calling Mick Jagger's personal assistant pretending to be a photo editor from Vogue.

The trick worked, and Zagaris was able to photograph a few of the band's first shows during their '72 tour. Zagaris described the rowdy experience in his book as "one of the last tours where the backstage life was everything everyone had ever imagined and much more."

According to Zagaris, Roger Daltrey is "the heart" of The Who. "When he took the stage he was a dynamo always in motion, looking like a young Adonis," Zagaris wrote.

However it's Pete Townshend that is "the soul" of the band, Zagaris said. Feeling claustrophobic during this show due to the psychedelic drugs he had taken with drummer Keith Moon, Zagaris moved up to a balcony. He almost missed this shot of Townshend throwing his guitar into the air.

If a newborn baby is too large or a woman's pelvis too narrow, it can be dangerous or deadly.

In theory, these are the sorts of characteristics that evolutionary pressures might make less common over time.

And yet, as researchers point out in a study published December 5 in the journal Proceedings of the National Academy of Sciences, obstructed labor caused by these traits still occurs pretty frequently (3-6% of births worldwide, according to an analysis of World Health Organization data).

The researchers conclude that there are certain evolutionary factors working against each other to keep these rates high. But more controversially, they conclude that more Cesarean section (C-section) births could be changing the balance of these factors and increasing the rates of obstructed labor. Still, there's reason to be skeptical about how much we know here.

In the paper, the researchers explain that competing pressures may cause these high rates of obstructed labor in the first place. On the one hand, higher birth weights and brain sizes are advantageous to newborns, right up until they are too big to fit through the birth canal. At the same time, since the genes that affect the size of the human pelvis come from both men and women and the researchers think there may be advantages to not developing ever-wider hips, that space hasn't become constantly wider to support larger babies.

The modern change that they predict is that C-sections make it easier to pass on the genes that would account for a small birth canal, potentially increasing rates of these potentially dangerous births.

According to a model the researchers created, they predict that C-sections may have caused these cases of obstructed labor to become 10 to 20% more common since roughly the 1950s, going from affecting about 30 out of every 1,000 births to affecting 33-36 out of every 1,000 births. (They don't actually know whether these rates have gone up, but they expect that if their model is correct, they have.)

"Without modern medical intervention such problems often were lethal and this is, from an evolutionary perspective, selection," Philipp Mitteroecker, a theoretical biologist at the University of Vienna and lead author of the study, told the BBC.

But of course, showing evolutionary changes in a short time span — about 60 years — is very difficult. Most evolutionary change occurs on scales of thousands or even millions of years, though in small populations it can happen more quickly. In addition, it's hard to know if obstructed labor is in fact becoming more common at all, and if so, it's even harder to know if that is strictly the result of C-sections.

What the data shows

C-sections have been a part of the human birth process for thousands of years. Greek mythology, ancient Hindu and Egyptian texts, Chinese etchings, and Roman history includes references to these types of births. But the modern era of safe and common C-sections began much more recently, after the development of antibiotics and after births in hospitals became the norm.

But the majority of C-sections do not occur because of obstructed labor, meaning that a rise in the number of C-sections doesn't necessarily mean these rates have gone up.

If obstructed labor occurs in 3% of births (or, if rates have increased, 3.3-3.6%), that still only accounts for a very small percentage of all of the C-sections performed. In the US, close to a third of all births happen by C-section. (Researchers say that ideally, these rates should be closer to 19%.) Many C-sections are the result of medical necessity caused by factors like obesity and diabetes. Others have to do with obstetrics ward policies or — perhaps — financial incentive or fear of malpractice lawsuits. In other words, obstructed labor is not the main factor here.

So are C-sections changing evolution? Maybe.

The researchers here simply say that their model can explain why obstructed labor persists as part of the human condition and they say it predicts how C-sections could make this more common.

It's certainly possible, likely, that a change in the way large numbers of people give birth has some effect on humanity.

"It would never occur to me that cesarean sections would not have an effect," biological anthropologist Karen Rosenberg tells The Daily Beast. "The idea that human behavior affects our evolution is a central idea in understanding of evolution. All kinds of things — when we cook our food, when we share food, when we build shelters — everything we do as cultural animals has the potential to affect our biology."

But for now, we don't even know that obstructed labor is becoming more common. There's probably some effect or multiple effects that C-sections are having on humanity, but without more data, we can't specifically say what they are.

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