Author: Futurity (National Geo)

We need to think about the human aspect of using AI in our everyday lives and how it will influence the ways in which we perceive and interact with one another, says communication scholar Jeff Hancock.

Since its public launch in November 2022, ChatGPT has captured the world’s attention, showing millions of users around the globe the extraordinary potential of artificial intelligence as it churns out human-sounding answers to requests ranging from the practical to the surreal.

It has drafted cover letters, composed lines of poetry, pretended to be William Shakespeare, crafted messages for dating app users to woo matches, and even written news articles, all with varying results.

Emerging out of these promising applications are ethical dilemmas as well. In a world increasingly dominated by AI-powered tools that can mimic human natural language abilities, what does it mean to be truthful and authentic?

Hancock has been tackling this issue and the impact of AI on interpersonal relationships in his research.

Hancock argues that the Turing test era is over: Bots now sound so real that it has become impossible for people to distinguish between humans and machines in conversations, which poses huge risks for manipulation and deception at mass scale. How then can these tools be used for good and not harm is a question that has Hancock and others worried.

While he sees the potential of AI to help how people do their work more effectively, Hancock sees pitfalls as well. Ultimately, he says, our challenge will be to develop AI that supports human goals and to educate people how best to use these new technologies in effective and ethical ways.

For several years now, Hancock has been examining how AI-mediated communication is transforming—and potentially, undermining—interpersonal relationships.

Here, he explains some of the challenges tools like ChatGPT pose and how they will shape our lives going forward:

Due to their feed, chicken and farmed salmon have remarkably similar environmental footprints, research finds.

The key is in the feed, says marine ecologist Ben Halpern, director of the University of California, Santa Barbara’s National Center for Ecological Analysis & Synthesis, and an author of a paper in the journal Current Biology.

In an effort to tease out opportunities for reducing the substantial environmental pressures of global food production, he and colleagues took a deep look at how we raise these two highly popular animals for consumption, focusing in particular on dynamics between land and sea.

“Chicken are fed fish from the ocean, just as are salmon, and salmon are fed crop products like soy, just as are chicken,” Halpern says regarding industrially farmed broiler chickens, and farmed salmonids (salmon, marine trout, and char). In addition to land-based crops, chickens are fed fishmeal and fish oil; while salmon, which typically eat other fish, are farmed with land-based feed, such as oil crops, soybeans, and wheat. “In a sense,” he notes, “we really do have ‘chicken of the sea.’”

The researchers found that 95% of the cumulative environmental footprint of these two items (greenhouse gas emissions, nutrient pollution, freshwater use, and spatial disturbance) is concentrated on less than 5% of the planet, with 85.5% spatial overlap between the two products, due mostly to shared feed ingredients. According to the study, the total cumulative pressures from chicken production is highest in the United States, China, and Brazil.

For fish, the highest cumulative pressures are found off the coasts of Chile, Mexico, and China, with some pressure on land due to salmon aquaculture. Additionally, the researchers found that while chicken has nine times the environmental footprint of farmed salmon, it has 55 times more production than salmon, an efficiency due largely to the very fast reproductive cycle of chickens—six to eight weeks to reach slaughter weight versus one to two years for salmon.

Within that 5% of the planet that bears the environmental pressures of chicken and salmon production, there are variations in the farming methods’ environmental efficiencies. In the case of chicken, for instance, the US (the world’s top producer of chicken) and Brazil (second largest) are more efficient than China (third largest). There are also variations between environmental pressures relative to the amount of salmon produced that differ by geography, indicating opportunities to improve efficiencies while minimizing environmental impacts.

Chicken and salmon are among the most popular sources of protein and, according to the researchers, are relatively environmentally efficient in comparison to other animal protein production such as beef and pork. However, the magnitude of their production, and their overlap in terms of environmental footprint raises interesting questions about the subtle connections between marine and land protein production, which, in turn, could provide opportunities for promoting sustainability. At the same time, the study underscores the importance of integrating food policies across realms and sectors to advance food system sustainability, according to the researchers.

“We got really interested in understanding how these two critically important and dominant foods affect our planet and how they compare,” Halpern says. “I knew from past research I’ve been part of that what we feed animals is a key part of what determines their environmental footprint, but I really didn’t expect chicken and farmed salmon to be so similar. The old adage that ‘we are what we eat’ applies to farm animals too!”

Source: UC Santa Barbara

A psychologist has advice for how to find and foster love, including how to get the most out of online dating.

Social psychologist Harry Reis was instrumental in launching the field of relationship science. For nearly five decades, the University of Rochester professor has been studying close relationships, theories of intimacy, and personal attachment styles.

Here, Reis shares his science-backed advice on how to find—and keep—love:

Which is better: Online dating or traditional dating?

Dating apps or sites are not necessarily better equipped at introducing you to higher-quality candidates than meeting someone in public or through your social circles, says Reis. But they do give you a lot more options. Where else would you be able to meet two or three dozen people a week?

By now, the apps have largely given up on formulating algorithms that claim to match perfect couples. Instead, they offer dating options based on factors such as location, interests, life goals, and more, expanding the “field of eligibles,” as Reis calls it.

“If I were single, I would definitely be using those sites,” he says.

According to a recent report by the Pew Research Center, online dating is much more common among younger generations, with 53% of adults under 30 saying they have used dating sites or apps. One in five adults under 30 say they met their current spouse or partner on a dating site or app, as do about a quarter of partnered lesbian, gay, or bisexual adults.

Are marriages that result from online dating any better than other marriages? Reis doubts it, since studies point in both directions. The bigger issue, according to him, is that the research isn’t properly designed to answer this question in the first place. In addition, emerging and changing technologies for dating—virtual reality dating, for example—are outpacing research on the subject.

Reis’s main takeaway in the current age of digital dating? “You have to kiss a lot of frogs to find a prince,” he says. “And that’s fine.”

How you can get the most out of online dating?

First, take some of the information in online profiles with a grain of salt, says Reis, who has studied the effectiveness of online dating. “Women, on average, claim to be a few years younger, and men say they’re a few inches taller,” he says, but these are just averages—they don’t mean that everyone is dissembling.

That aside—don’t reject candidates out of hand just because they don’t seem to share your interests, Reis and coauthors write in their critical analysis of online dating. Instead, weed out only those who are clear no’s from the get-go—those who live thousands of miles away, or simply live on the wrong side of your core values. Then, connect with as many possible partners and go on as many dates as you can, advises Reis. Make some semi-random choices and see where that takes you. Don’t make assumptions about the person simply based on what they claim in their online profile; rather, pick up the phone and find out what they’re like firsthand.

Keep in mind, too, that similarities matter to an extent but are far from a guarantee for happy relationships. In fact, connecting with someone who has different interests from your own can be a way of growing—something that psychologists explain via the self-expansion model. Instead of looking for a person who likes baseball as much as you do, try being open to something new. “If somebody loves ballet, and you don’t know much about ballet and have never tried going to a performance, that could turn out to be really interesting,” offers Reis.

But the biggest mistake in online dating? Putting too much emphasis on appearances.

Of course, attractiveness matters—that’s true whether meeting online or in person. But most people use looks as the main criterion when making choices online about whom they want to get to know better, thereby weeding out possible good matches by mistake.

The other thing people get wrong, according to Reis, is processing the information about another person in a superficial way, without really giving much thought to what the other might be like and might be interested in.

In short: slow down when swiping. Take time to read, think, feel.

“Romantic chemistry is certainly elusive,” says Reis, who recently published a paper on interpersonal chemistry. “But it’s an exaggeration to claim it’s either there or not, based on a few minutes of interaction.”

Instead, chemistry is about forging a connection, a feeling of being on the same wavelength with another person. If someone opens up about what they find interesting and what’s important to them—and if the potential partner responds in a way that shows true listening—then a back-and-forth ensues.

“The feeling that the other person just ‘gets us’ is really emerging chemistry,” says Reis. That feeling, by the way, can be similar to what happens at the start of new (non-romantic) friendships.

More often than not, romantic chemistry emerges relatively quickly—although not necessarily instantly. Yet plenty of people go on first dates after connecting on a dating app, only to decide hastily that “we have no chemistry.” While there’s no magic number of minimum hours or dates to aim for, Reis recommends avoiding snap judgments.

Occasionally, chemistry between two people emerges much later. Some relationships can and do change, with a sense of connection turning a friendship into a romance. “Be on the lookout, but don’t expect magic to arrive out of thin air,” says Reis.

Avoid the ‘suffocation model’

Keep your expectations grounded. Perfection is the enemy of good. If you want a partner for life, pay less attention to looks and don’t expect the impossible, advises Reis.

In the 1950s, he says, people frequently found their partner in their own neighborhood, or in their religious or social groups. But in today’s digitally connected world, people tend to have higher expectations for potential partners. “It’s been called the ‘suffocation model of relationships’ by researchers, in that we want the other person to be our sexual partners, our best friends, our confidants, our co-parents, and our financial partners. We want them to be everything to us. And that’s an awfully high expectation for us humans to live up to.”

During one of Reis’s studies, a participant told him that they knew exactly what they wanted their future partner to be. And if the participant couldn’t find someone who was 100% like that, they’d rather be single.

In some ways, online dating has contributed to the false idea of finding a perfect match by serving up a seemingly endless supply of options. “I don’t think that 100% person exists for anybody,” Reis says. “If you are holding out for perfection, you may very well find yourself priced out of the market.”

Meanwhile, dating during the pandemic has created additional challenges. Seven in ten Americans, who were single and looking for a partner, said their dating lives weren’t going well, according to a 2022 Pew Research Center survey.

Make small tweaks for big improvements

You’ve found your partner for life (or, at least, for now). How do you make sure mutual love endures? What makes couples stay together—for months, years, decades, or forever—and remain happy and fulfilled? Plenty has been written on the topic in books, magazines, blogs, and other outlets. But what does the research say?

One of the critical factors, according to Reis, is the ability to resolve disagreements in a cooperative and supportive way without creating further hurts. It’s “a huge one” that’s been shown in just about every study that’s been done on the topic.

Another important strategy is to share positive events with your partner. Reis has studied both the intrapersonal and interpersonal benefits—that is, the advantages for both the “sharer” and the partner—of communicating positive experiences and letting your partner know that you are excited for them. So, why does this strategy work? Because we all like when good things happen to us—such as getting a promotion at work, passing a big test, setting a personal best in bowling or at a 5K race—and we want to share that experience with our partners.

In a set of experiments, Reis found that when people talked about personal positive events with others, they felt even happier, beyond simply the uplifting effect of the event itself. And when a partner responded enthusiastically to the sharing of the other’s good news, the relationship fared better with increased well-being for both partners, greater intimacy, and higher daily marital satisfaction.

Research shows that another seemingly trivial, yet nonetheless effective, way of building connections with a partner is having the “how was your day” conversation, where partners listen to one another, ask questions, allow for elaboration, and show empathy or enthusiasm.

“The point is that you’re really listening to your partner, that you’re really engaging,” says Reis. “It’s not so much about the issue of the conversation as it is about the engagement, the sense of making time for each other, and connecting in those moments.”

When people first start dating, connecting happens naturally and frequently. As time goes on—and especially once couples are married or have been living together for a while—it’s easy to lose that attentiveness in the daily humdrum of work, household responsibilities—and for some—the raising of children. But it’s these little things that make a big difference, says Reis, and that contribute to feeling understood by your partner.

Shared hobbies matter

While spouses (or partners) don’t have to be clones of each other or do everything together, they need to be on the same page about where they want their lives to go. Part of that means enjoying some degree of shared recreation. “If you’re always doing things separately, you’re not building connections,” Reis points out.

There’s important research on so-called “novel” and “arousing activities,” which has shown that couples do well when they are taking up a new hobby together. It typically should be something that’s a bit more active, says Reis, like learning to ski, taking cooking lessons, or trying dance classes together—something that introduces an element of novelty for both participants.

Particularly in this COVID era, many couples feel their lives have become stagnant. “The same thing every night: they have dinner and then they watch Netflix. That can get awfully tiresome,” says Reis.

Doing new things together that are fun and interesting can help keep a marriage or a partnership vital. “Even something as mundane as going to the movies together and then talking about it,” says Reis, pointing to research by colleague Ronald Rogge, which shows that couples who watched romantic comedies together and talked about them afterward reduced their risk of divorce.

The evolving nature—and science—of love

Even as social psychologists and others continue to learn more about the intricacies of human love and intimacy, it’s important to remember that research in this area is ongoing—and increasingly reflective of changing norms and practices, from virtual reality dating to ethical non-monogamy.

Reis notes that much of the literature on relationship research to date is predominantly based on “WEIRD samples,” participants who belong to groups that are western, educated, industrialized, rich, and democratic. But, he says, more work is being done with married same-sex couples—and so far, the findings among same-sex couples seem, with a few exceptions, very much similar to those of mixed-sex couples.

The one thing couples can do right now to improve their relationship

It depends, of course, on the strengths and weaknesses of each particular relationship. But if he had to pick one thing, Reis says, it would be this one: “Make it clear that your relationship is one of your highest priorities. And really act on that. Make connecting in the relationship not the thing you do after everything else is done.”

How do you signal that importance? Set aside time for a regular date night, for example. Really talk and listen to each other, perhaps while doing a chore together—such as washing the nightly dishes or walking the dog. Send your partner an affectionate text during the day to let them know they are on your mind. And don’t forget the importance of physical affection.

Beware that problems have a tendency to swamp us, he cautions. “The difficulties, the stresses, the disagreements, all tend to dominate our attention. That’s what we humans do—we pay attention to what’s going wrong,” says Reis. That negative bias can lead people to forget what was fun about their relationship in the first place.

“Building in those little positive moments is an easy way of reminding oneself and one’s partner that there’s something good here,” says Reis.

Source: University of Rochester

We sometimes treat the Black experience as though it is peripheral to the American experience, when in fact it is central. I wrote a newspaper article long ago now, the headline of which was “Black History is American History.” And the point of it was that while Black History Month, (which started as Black History Week), is a good thing, the ultimate endpoint should be that we have issues of Black history fully integrated into American history. That should be the endpoint, to understand the extent to which the central issues involving the nature of our democracy have played out in a racial context, because the struggle with racism has defined our nation. We’ve been struggling with racism since the very beginning. African American Studies is a step in the direction of the full integration of the Black experience into the American experience.

There has been some controversy about Florida Governor DeSantis and his railing against this new AP course. The College Board released an official curriculum that, by news accounts, has been revised, stripped of much of the subject matter that angered DeSantis and conservatives, including critical race theory, LGBTQ issues, and the Black Lives Matter movement.

What people seem to be doing is taking positions based on their identity, rather than their knowledge of the facts, whether they’re DeSantis or one of his supporters or one of his critics. That said, the appearance here is that the College Board made a decision for political reasons, rather than substantive, pedagogical, or curriculum-oriented reasons. And that’s a bad thing.

But I should also say that the fact that the outcome here, if it’s politically motivated, may be a bad outcome, doesn’t mean that the concerns that prompted the criticism by DeSantis are wholly illegitimate. And this is what I think people miss. There may still be some legitimate reasons that are giving rise to proposed amendments, some legitimate things that people are reacting to. This is not a debate about what’s true versus what’s false. It’s a debate about the ways in which teachings of history can create narratives about society. Evidently the narrative of the nation embedded in the prior version is something that DeSantis and others were opposed to because it created a sort of orthodoxy about the nation that they could not support.

New research shows how the atoms in perovskites move in response to light.

The breakthrough in visualization supports the researchers’ efforts to squeeze every possible drop of utility out of perovskite-based materials, including solar cells, a long-standing project that only recently yielded an advance to make the devices far more durable.

The study in Nature Physics details the first direct measurement of structural dynamics under light-induced excitation in 2D perovskites. Perovskites are layered materials that have well-ordered crystal lattices. They are highly efficient harvesters of light that are being explored for use as solar cells, photodetectors, photocatalysts, light-emitting diodes, quantum emitters, and more.

“The next frontier in light-to-energy conversion devices is harvesting hot carriers,” Aditya Mohite, a corresponding author of the study. “Studies have shown that hot carriers in perovskite can live up to 10-100 times longer than in classical semiconductors. However, the mechanisms and design principles for the energy transfer and how they interact with the lattice are not understood.”

Hot carriers are short-lived, high-energy charge carriers, either electrons for negative charges or electron “holes” for positive charges, and having the ability to harvest their energy would allow light-harvesting devices to “surpass thermodynamic efficiency,” says Mohite, an associate professor of chemical and biomolecular engineering in Rice University’s George R. Brown School of Engineering.

Mohite and three members of his research group, senior scientist Jean-Christophe Blancon and graduate students Hao Zhang and Wenbin Li, worked with colleagues at the SLAC National Accelerator Laboratory to see how atoms in a perovskite lattice rearranged themselves when a hot carrier was created in their midst. They visualized lattice reorganization in real time using ultrafast electron diffraction.

“Whenever you expose these soft semiconductors to stimuli like electric fields, interesting things happen,” Mohite says. “When you generate electrons and holes, they tend to couple to the lattice in unusual and really strong ways, which is not the case for classical materials and semiconductors.

“So there was a fundamental physics question,” he says. “Can we visualize these interactions? Can we see how the structure is actually responding at very fast timescales as you put light onto this material?”

The answer was yes, but only with a strong input. SLAC’s mega-electron-volt ultrafast electron diffraction (MeV-UED) facility is one of the few places in the world with pulsed lasers capable of creating the electron-hole plasma in perovskites that was needed to reveal how the lattice structure changed in less than a billionth of a second in response to a hot carrier.

“The way this experiment works is that you shoot a laser through the material and then you send an electron beam that goes past it at a very short time delay,” Mohite explains. “You start to see exactly what you would in a TEM (transmission electron microscope) image. With the high-energy electrons at SLAC, you can see diffraction patterns from thicker samples, and that allows you to monitor what happens to those electrons and holes and how they interact with the lattice.”

The experiments at SLAC produced before-and-after diffraction patterns that Mohite’s team interpreted to show how the lattice changed. They found that after the lattice was excited by light, it relaxed and literally straightened up in as little as one picosecond, or one-trillionth of a second.

Zhang says, “There’s a subtle tilting of the perovskite octahedra, which triggers this transient lattice reorganization towards a higher symmetric phase.”

By demonstrating that a perovskite lattice can suddenly become less distorted in response to light, the research showed it should be possible to tune how perovskite lattices interact with light, and it suggested a way to accomplish the tuning.

Li says, “This effect is very dependent on the type of structure and type of organic spacer cation.”

There are many recipes for making perovskites, but all contain organic cations, an ingredient that acts as a spacer between the materials’ semiconducting layers. By substituting or subtly changing organic cations, researchers could tailor lattice rigidity, dialing it up or down to alter how the material responds to light, Li says.

Mohite says the experiments also show that tuning a perovskite’s lattice alters its heat-transfer properties.

“What is generally expected is that when you excite electrons at a very high energy level, they lose their energy to the lattice,” he says. “Some of that energy is converted to whatever process you want, but a lot of it is lost as heat, which shows in the diffraction pattern as a loss in intensity.

“The lattice is getting more energy from thermal energy,” Mohite says. “That’s the classical effect, which is expected, and is well-known as the Debye-Waller factor. But because we can now know exactly what’s happening in every direction of the crystal lattice, we see the lattice starts to get more crystalline or ordered. And that’s totally counterintuitive.”

A better understanding of how excited perovskites handle heat is a bonus of the research, he says.

“As we make devices smaller and smaller, one of the biggest challenges from a microelectronics perspective is heat management,” Mohite says. “Understanding this heat generation and how it’s being transported through materials is important.

“When people talk about stacking devices, they need to be able to extract heat very fast,” he says. “As we move to new technologies that consume less power and generate less heat, these types of measurements will allow us to directly probe how heat is flowing.”

The research had support from the Department of Energy, the Office of Naval Research, the Robert A. Welch Foundation, and the Academic Institute of France.

Source: Rice University

People who share a political ideology have more similar “neural fingerprints” of political words and process new information in similar ways, according to a new analysis.

Take the word “freedom,” for example, or a picture of the American flag, or even the 2020 US presidential election. A person who identifies politically as liberal vs. one who identifies as conservative will likely have opposing interpretations when processing this information—and the new research helps to explain why.

While previous theories posited that political polarization results from selective consumption (and over-consumption) of news and social media, a team led by researchers at Brown University hypothesized that polarization may start even earlier.

The new study appears in Science Advances.

Individuals who share an ideology have more similar neural fingerprints of political words, experience greater neural synchrony when engaging with political content, and their brains sequentially segment new information into the same units of meaning.

In this way, the researchers say, they show how polarization arises at the very point when the brain receives and processes new information.

“This research helps shed light on what happens in the brain that gives rise to political polarization,” says senior study author Oriel FeldmanHall, an associate professor of cognitive, linguistic, and psychological sciences who is affiliated with the Carney Institute of Brain Science at Brown University. Daantje de Bruin, a graduate student in FeldmanHall’s lab, led the research and conducted the data analysis.

Previous research from FeldmanHall’s lab showed that when watching a potentially polarizing video about hot-button issues like abortion, policing, or immigration, the brain activity of people who identified as Democrat or Republican was similar to the brain activity of people in their respective parties.

That neurosynchrony, FeldmanHall explains, is considered evidence that the brains are processing the information in a similar way. For this new study, the researchers wanted to get an even more detailed picture of why and how the brains of people in the same political party are able to sync up.

To do that, the team used a range of methods that they say have never before been used in conjunction with each other. They conducted a series of experiments with a group of 44 participants, equally split among liberals and conservatives, who agreed to perform various cognitive tasks while undergoing functional magnetic resonance imaging (fMRI), which measures the small changes in blood flow that occur with brain activity.

This research helps shed light on what happens in the brain that gives rise to political polarization.

Participants first completed a word reading task in which they were presented with single words (e.g., “immigration,” “abortion”) and asked to determine whether the word was political or non-political (indicated via a button press). Then the participants watched a series of videos, including a neutrally worded news clip on abortion and a heated 2016 vice presidential campaign debate on police brutality and immigration. During the experiments, the participants’ brain activity was measured using fMRI.

One of the methods the researchers used is called representation similarity analysis. When a person sees a simple, static image, like a word, the brain will represent that word with certain activity patterns.

“You can think of it as the brain representing the word by firing neurons in a certain way,” FeldmanHall says. “It’s almost like a fingerprint—a neural fingerprint that encodes the concept of that word within the brain.”

She added that since neural activity patterns store information about the world, how the brain represents this information is considered a metric for how that information is interpreted and used to steer behavior and attitudes.

In the study, the participants were exposed to words that are often politicized, like “abortion,” “immigration” and “gangs,” as well as more ambiguous words, like “freedom”.

The researchers found by analyzing the fMRI data that the neural fingerprint created by a liberal brain is more similar to other liberal brains than the neural fingerprint created by a conservative brain, and vice versa. This is important, FeldmanHall says, because it shows how the brains of partisans are processing information in a polarized way, even when it’s devoid of any political context.

The researchers also used a newer methodology called neural segmentation to explore how the brains of people who identify with a particular party bias the interpretation of incoming information. Brains are constantly receiving visual and auditory input, FeldmanHall says, and the way the brain makes sense of that continuous barrage of information is to separate it into discrete chunks, or segments.

“It’s like dividing a book of solid text into sentences, paragraphs, and chapters,” she says.

The researchers found that the brains of Democrats separate incoming information in the same way, which then gives similar, partisan meanings to those pieces of information—but that the brains of Republicans segment the same information in a different way.

The researchers note that individuals who shared an ideology had more similar neural representations of political words and experienced greater neural synchrony while watching the political videos, and segmented real-world information into the same meaningful units.

“The reason two liberal brains are synchronizing when watching a complicated video is due in part to the fact that each brain has neural fingerprints for political concepts or words that are very aligned,” FeldmanHall explains.

This explains why two opposing partisans can watch the same news segment and both believe that it was biased against their side—for each partisan, the words, images, sounds, and concepts were represented in their brain in a different way (but similar to other partisans who share their ideology). The stream of information was also segmented out in a different format, telling a different ideological story.

Taken together, the researchers conclude, the findings show that political ideology is shaped by semantic representations of political concepts processed in an environment free of any polarizing agenda, and that these representations bias how real-world political information is construed into a polarized perspective.

“In this way, our study provided a mechanistic account for why political polarization arises,” FeldmanHall says.

The researchers are now focusing on how this explanation of polarization can be used to combat polarization.

“The problem of political polarization can’t be addressed on a superficial level,” FeldmanHall says. “Our work showed that these polarized beliefs are very entrenched, and go all the way down to the way people experience a political word. Understanding this will influence how researchers think about potential interventions.”

Additional contributors to this research include Pedro L. Rodríguez from the Center for Data Science at New York University and Jeroen M. van Baar from the Netherlands Institute of Mental Health and Addiction.

Source: Brown University

New research provides insight into the unique sex lives of giraffes, their reproductive behavior, and how their anatomy supports that behavior.

It can be hard to know if someone is really into you. Sometimes, you get hints—a certain look or smile, a nervous blush, or flirtation. Giraffes get none of that.

They have no set breeding season. They don’t go into heat, like dogs or cats. They don’t make mating calls or provide visual cues of sexual readiness. So how is a male giraffe to know his advances will be well-received? In short: pee, pheromones, and a gentle nudge.

The new study in the journal Animals describes how male giraffes test females for sexual receptivity.

First, the bulls provoke the females to urinate by nudging them and sniffing their genitalia. If the female is open to his invitation, she widens her stance and pees for about 5 seconds while the male takes the urine in his mouth. He then curls his lip, inhaling with an open mouth—an act called flehmen that transports the female’s scent and pheromones from his oral cavity to the vomeronasal organ.

The study provides the most precise understanding yet of how flehmen occurs with giraffes’ anatomy. While flehmen is common among many animals, including horses and cats, most mammals wait until urine is on the ground to investigate. The giraffe, however, is not built for such explorations.

“They don’t risk going all the way to the ground because of the extreme development of their head and neck,” says lead author Lynette Hart, a professor of population health and reproduction in the School of Veterinary Medicine at the University of California, Davis. “So they have to nudge the female, effectively saying, ‘Please urinate now.’ And often she will. He has to elicit her cooperation. If not, he’ll know there’s no future for him with her.”

Hart and her coauthor and husband, Benjamin Hart, professor emeritus with the School of Veterinary Medicine, witnessed this behavior on multiple research trips to Namibia’s Etosha National Park.

Dotted among the park’s western side were large watering holes, where dozens of giraffes would congregate. Lynette called it “a dream come true” for observing giraffes. “So often you see a few in the distance, not an up-close view of what they’re doing,” she says.

Benjamin Hart had studied how flehmen behavior worked within the anatomy of other animals, including goats. During their trips to East Africa, the Harts suspected a similar process was underway for giraffes.

“This is part of their reproductive behavior,” Benjamin Hart says. “This adds to our understanding of what giraffes are doing as they accumulate around a water hole. People love watching giraffes. I think the more the public understands about them, the more interested they’ll be in their conservation.”

The Harts also describe in the study previously undocumented giraffe behaviors, from chewing bones to potentially mourning their dead:

• Earlier studies noted that osteophagia, or chewing bones, was unusual for giraffes. But the Harts observed many instances of giraffes seeking and chewing bones, and sometimes getting them lodged in their mouths.
• After a giraffe had been killed by two lions, the Harts also witnessed for several days a steady procession of giraffes arriving to investigate the body.
• The Harts experienced another significant observation when they heard a bull emit a loud growl on different occasions. It was most likely a warning call, as it drove away most surrounding giraffes. Giraffes are typically very quiet and were once even thought to be mute.

The research received no direct external funding. Financial assistance for travel and accommodations was provided by UC Berkeley’s University Research Expeditions Program.

Source: UC Davis

A new system for tropical disease research spares people and animals mosquito bites.

Researchers are working to take some of the pain out of studying the feeding behavior of mosquitoes. The insects’ bites can spread diseases like malaria, dengue, and yellow fever, but setting up experiments to examine their behavior can take a big bite out of lab budgets.

“Many mosquito experiments still rely on human volunteers and animal subjects,” says Kevin Janson, a graduate student in bioengineering at Rice University and lead coauthor of a study in Frontiers in Bioengineering and Biotechnology. Live subject testing can be expensive, and Janson says the “data can take many hours to process.”

So he and his coauthors found a way to automate the collection and processing of that data using inexpensive cameras and machine-learning software. To eliminate the need for live volunteers, their system uses patches of synthetic skin made with a 3D printer. Each patch of gelatin-like hydrogel comes complete with tiny passageways that can be filled with flowing blood.

To create the stand-ins for skin, the team used bioprinting techniques that were pioneered in the lab of former Rice professor Jordan Miller.

For feeding tests, as many as six of the hydrogels can be placed in a transparent plastic box about the size of a volleyball. The chambers are surrounded with cameras that point at each blood-infused hydrogel patch. Mosquitos go in the chamber, and the cameras record how often they land at each location, how long they stay, whether or not they bite, how long they feed, etc.

Researchers in the laboratory of Dawn Wesson, associate professor of tropical medicine at Tulane University, tested the system. Wesson’s research group has facilities for breeding and testing large populations of mosquitoes of varying species.

In the proof-of-concept experiments featured in the study, Wesson, Janson, and coauthors used the system to examine the effectiveness of existing mosquito repellents made with either DEET or a plant-based repellent derived from the oil of lemon eucalyptus plants. Tests showed mosquitoes readily fed on hydrogels without any repellent and stayed away from hydrogel patches coated with either repellent. While DEET was slightly more effective, both tests showed each repellent deterred mosquitoes from feeding.

Omid Veiseh, the study’s corresponding author and an assistant professor of bioengineering at Rice, says the results suggest the behavioral test system can be scaled up to test or discover new repellents and to study mosquito behavior more broadly. He says the system also could open the door for testing in labs that couldn’t previously afford it.

“It provides a consistent and controlled method of observation,” Veiseh says. “The hope is researchers will be able to use that to identify ways to prevent the spread of disease in the future.”

Wesson says her lab is already using the system to study viral transmission of dengue, and she plans to use it in future studies involving malaria parasites.

“We are using the system to examine virus transmission during blood feeding,” Wesson says. “We are interested both in how viruses get taken up by uninfected mosquitoes and how viruses get deposited, along with saliva, by infected mosquitoes.

“If we had a better understanding of the fine mechanics and proteins and other molecules that are involved, we might be able to develop some means of interfering in those processes,” she says.

The Robert J. Kleberg, Jr. and Helen C. Kleberg Foundation supported the research.

Source: Rice University