Erin Ross

Ancient engravings depict dogs on leashes

A dog carving found on a cliff in M.Guagnin. Credit: Journal of Anthropological Archaeology, 2017

Ancient sandstone engravings found in the Arabian desert depict dogs wearing leashes, according to a paper published Thursday in the Journal of Anthropological Archaeology and reported by David Grimm at Science.

Why it matters: It's difficult to date these carvings, but "based on the sequence of carving, the weathering of the rock, and the timing of switch to pastoralism" the pictures are likely 8,000-9,000 years old, writes Grimm, who notes that this would make them the oldest known depictions of dogs.

Modern resemblance: The dogs depicted have curly tails, like the Canaan dogs that live in the Middle East today.

Yes, but before the age of these engravings can be confirmed, they'll need to be tied to a well-dated archaeological site. Melinda Zeder, an archaeologist at the Smithsonian Institute of Natural History tells Grimm doing so could be difficult because "the archaeological record in this region is really spotty." Even if these aren't the oldest dog depictions we've found, they're definitely the oldest of leashes.


How bees decode each others' dances

The three neurons involved in deciphering the waggle dance. Image: Hidetoshi Ikeno / University of Hyogo

Scientists have mapped some of the neurons that let bees talk by dancing.

Why it matters: Bees, who accomplish impressive things despite their tiny stature, have become models for understanding cognition. Scientists study how they navigate and recognize faces — and now, how they share information. "We're starting to understand how a fairly simple neural system, like a bee's, can solve a complex task like communication," says Thomas Wachtler, a researcher at the Ludwig Maximilian University of Munich and an author on the study.

Bees tell each other how to find pollen-laden flowers using the 'waggle dance.' It's incredibly precise, and can pinpoint a flower miles away. A bee stomps and vibrates her wings and waggles her abdomen while walking in a straight line, then circles back to the start and does it again. The angle she moves says which way to go. The amount of time she wags tells the distance. Other bees follow the waggle map.

The catch: Hives are pitch-black. The observing bees don't see the dance — they hear and feel it.

Researchers already knew which neurons the bees used to feel vibrations, and they knew about the dance. But no one had looked at how the two interacted.

How they did it: Wachtler, along with Hiroyuki Ai and his colleagues at Fukuoka University and the University of Hyogo, drummed the beat of an artificial waggle dance to a bee, and measured signals from the neurons. At the center of the brain's response were three neurons: the first starts or stops the second in response to sound – so that measures the time period of the waggle. The purpose of the third isn't clear yet, but since it receives signals from both of the bee's antennae, Wachtler thinks it helps the observers track where the dancing bee is in space, so they can determine the angle of the waggle.


New stem cell research offers promise — and raises questions

Illustration: Rebecca Zisser / Axios

New advances in stem cell research have the potential to save lives – but not necessarily for the reasons people think. In the late 90s and early 2000s, scientists and the press heralded the promise of these cells that appeared to have the ability to become whatever type of cell was needed to replace or fix damaged tissues. But major advances were slow to come, and the hype faded.

What's happening now: Instead of flashy, morphing cells, the stem cell therapies of today are much more subtle, work in unexpected ways, and it's not always clear why. Still, these advances are promising, so much so that today the FDA released a newly restructured framework for regenerative medicine, including stem cells, to help expedite applications for new therapies.

Background: Stem cells are cellular blank slates. They take cues from their environment and permanently become a more specialized kind of cell. Some used in medicine do come from fetuses, but many persist into adulthood and are also used in some therapies:

  • Bone marrow stem cells, for example, can become blood, cartilage, or bone cells.
  • And, skin or blood cells can be re-programmed back into stem cells called induced pluripotent stem cells.

What's new: Research has steadily chugged along away from the limelight, "which is honestly how we prefer it," says neuroscientist Evan Snyder of UC San Diego, who admits some responsibility for the hype of the early-aughts. Small advances have accumulated, and there are currently several active human clinical trials using various types of stem cells to treat diseases, including:

  • ALS patients: With this neuromuscular disease, also called Lou Gehrig's disease, the brain cells called glia degrade. Stem cells injected into rats seem to protect these glia. Cedars-Sinai Medical Center has begun recruiting human patients for a phase 1 clinical trial.
  • Stroke patients: Bone marrow stem cells injected into the blood helped reduce movement difficulties in a trial of 31 recent stroke patients conducted by the University of Grenoble in France and the University of Baltimore in Maryland. The findings were presented in a poster at the Society for Neuroscience's annual meeting on Monday, and plans for a 400-patient study are underway.
  • Patients with spinal injuries: In a clinical trial of six patients with recent spinal injuries, all regained some motor function after receiving oligodendrocyte progenitor cells, a type of stem cell.
  • Buyer, beware: There are predatory clinics offering cure-all stem cell treatments, and the new guidelines issued today crack down on what the FDA calls "unscrupulous actors" under the guise of cutting-edge science. Outside of clinical trials, the FDA has only approved the use of a specific group of stem cells (from cord blood) for a specific set of blood-related illnesses.

What's next:

  • In injuries like gunshot wounds, the brain's own immune system turns on itself and attacks neurons, demolishing large regions of the brain. Research conducted by Shyam Gajavelli, a neurologist at the University of Miami, shows that human neuronal stem cells can prevent this process in rats, potentially by giving the immune system something other than brain cells to attack.
  • In a poster presented Monday at the Society for Neuroscience meeting, Gajavelli also reported stem cells protected rats from injury-related coordination problems. He says that more research is needed before they're ready for human trials, however.
A black box: Researchers agree that stem cells work to treat many diseases. However, "there's a sort of black box around the mechanism with stroke," says Thomas Zeffiro from the University of Maryland, who is involved with human trials on stroke and stem cells.
  • Part of the mystery is that in past stroke studies, it appears stem cells injected into the blood stream never reach the brain, but are instead processed in the spleen, according to Snyder. Despite the mechanistic mystery, the benefits of stem cells for stroke in lab animals are well-documented.
  • It's not just stroke. Although numerous trials have shown that stem cells can be effective treatments, in many cases the exact ways they work aren't yet clear. Snyder suspects that the therapeutic strength of stem cells might not lie in their abilities to heal, but in their abilities to protect:

"It could be anti-inflammation, it could be protective against scar formation, it could be building an extracellular matrix. It might not even be just one mechanism," Snyder says. '"I'd go so far as to say that almost any positive outcome seen in humans or animals is due to neuroprotection."

Why this is important: As several researchers noted, the FDA is understandably reluctant to approve new treatments if it isn't clear why they work. Until scientists better understand reasons different stem cell treatments seem to help with different diseases, this could limit the development of more effective, precise treatments.

One more thing: Although all these advances are significant and important, Snyder thinks there's an area of stem cell research that is even more promising – as tools that:

  • measure the progression of a disease
  • act as 'reporter cells' that alter as they move through the body in ways scientists can track.
  • can be used to study drug toxicity.
  • help researchers understand more about how development happens, from egg to embryo to full-blown life.

How India's colonial past shapes its science today

Illustration: Lazaro Gamio / Axios

Today, India hosts some of the world's top doctors and scientists. But the focus on global science sometimes neglects local needs and expertise, says Indian science journalist Padma Tata Venkata, who goes by Padma TV.

Axios spoke with her about the impact of the English on research in her country as part of a series of interviews about a movement to decolonize science. Highlights from the interview conducted via e-mail — and edited for length and clarity — are below.

What does decolonizing science mean to you?

Decolonizing science means acknowledging the scientific accomplishments of non-western ancient civilizations. Of course, all modern scientific theories and methods of observation, enquiry and validation hold and should continue to hold. But one should also be open to the existence of scientific knowledge in civilizations that preceded the present one in which the West dominates, and propagate the oft-repeated narrative that true scientific knowledge evolved only in the West.

India had advanced technology before colonization. Did that change?

In colonial India, the then rulers dismissed traditional knowledge systems and their contributions to science. Colonization also created arbitrary divisions of western scientific rationale, logic and technology versus eastern superstition and magic, which further devalued any genuine scientific knowledge present before the colonizers arrived.

An example from the Indian sub-continent is the ancient systems of medicine that existed before the introduction of the British system of medicine or allopathy. These include Ayurveda, Siddha systems, Unani from West Asia. These systems were slowly marginalized and de-recognized during colonial rule when only allopathy was recognized and only its practitioners were considered eligible for registration as doctors.

With imposition of English, additionally, other local languages started to get marginalized, which meant loss of valuable information available in local languages.

Does English colonization have an impact on science in India today?

By the time India became a free country in 1947, it was economically poor and, hence, had to struggle to balance its investments in a number of sectors such as agriculture, health, education and science. India and other newly free countries also ended up with low self-esteem, with systematic under-mining of their older scientific legacies and the fact they lost out on the 'Industrial Revolution' of the West. They felt the only way forward was to 'catch up' and obtain parity the West in science and technology, and overall development , and so they need to imitate the west.

Hence, an independent India adopted the Western model of speedy development, which meant some of its technological choices were also a result of global structures and global technology politics. A western- and techno-centric model of development also meant aligning its scientific priorities with prevailing western scientific trends and focus; and disregarding local priorities, needs. The heavy reliance on Western interpretation of technology and culture often disregards local knowledge systems, especially of local ecological and socio-economic conditions, which are not seen as 'technologically advanced'. This has also led to adoption of faulty technologies that led to severe ecological and environmental crisis.

How has this focus on Western scientific trends influenced the research that's done?

Grassroots innovations are examples of simple, frugal, niche-specific innovations which address a local need, and are often by people who have not studied science or are not PhDs and post-docs,. These innovations tailored to solve local problems and lack institutional support of elite scientific institutes whose research agenda is dictated, or at any rate, influenced by current research trends and priorities in advanced countries. The innovations are not mentioned in peer-reviewed scientific literature.

Over 100,000 ideas, innovations and traditional knowledge practices from India and abroad are documented by Honey Bee Network, founded by Anil Gupta, professor emeritus at Indian Institute of Management, Ahmedabad. To cite a few examples: a power-generating pumping machine, tractor-mounted maize sheller, an 'amphibious' bicycle that helps you peddle in water, a compost aerator, natural convection drier for agricultural products.


These spiders have the fastest biological clock seen yet

A species of spiny orb-weaver spider has a 19-hour circadian clock. Photo: ojogabonitoo / iStock

Three species of orb-weaving spiders may have the fastest biological clocks known in nature. Their circadian cycles range between 17.4 and 19.0 hours on average, instead of synchronizing with a 24-hour solar light cycle. The research, conducted at East Tennessee State University, was presented Sunday at the annual meeting of the Society for Neuroscience.

Why it matters: Their clock is so fast, it's unclear how the spiders survive. Studying extreme sleep-wake cycles and circadian clocks can help scientists understand the role these neurological timekeepers play in species survival and what causes our own rhythms to go awry due to disease.

Most research on fast circadian clocks has been done in deliberately-created mutant hamsters and fruit flies.

How they did it: Animals tend to maintain their natural circadian rhythm in the absence of light so the researchers exposed the spiders to constant dark. The spiders alternated between moving and resting in 17-19 hour loops, depending on the species.

Go deeper: The three species are Allocyclosea bifurca and Cyclosa turbinata , both types of trashline orb-weavers, and the spiny orb-weaver ( Gasteracanthea cancriformis). Researchers note that the spiders are most active late at night, in contrast with most nocturnal spiders, which are active early at night. It's unclear if this is related to their abnormally short circadian rhythm.

Language puts up barriers in science

Photo illustration: Axios Visuals

In classrooms in the U.S. and around the world, science is often taught as an idea that began with the Greeks. Now there is a growing movement calling for science to be decolonized, and to acknowledge the contributions and ideas of non-Western peoples.

At the World Conference of Science Journalists last month, South African science writer Sibusiso Biyela spoke about how language inequality can keep people — and ideas — out of science. Axios followed up with Biyela to ask whether colonization still influences science in South Africa today. The interview, edited for length and clarity, is below.

"Do you really understand something if you don't understand it in your own language?" Biyela asks.

Is science a universal concept?

Yes. Science is the same everywhere. We might call it different things, but it's the same laws applying to the whole universe and everywhere on Earth that human beings are.

Science is just a way of reasoning that everyone does. All cultures had to apply those concepts in order to survive. So when you repackage that and call it "science" in a different language, it seems foreign.

What was the first story you wrote in English and Zulu?

I was writing about the Meerkat project, a precursor to the Square Kilometer Array project, part of which is constructed in South Africa.

I was so excited about the project that I decided to write it both in English and my native language, Zulu. And while it was quite easy to write the English version, I had a problem writing a Zulu version. Every time that I got to a concept like a supernova or a black hole or a quasar, I'd need a whole paragraph to explain it. It didn't translate.

In the end, I wrote two entirely different stories. The English one focused on the project itself and what it will do. I used the Zulu version as a chance to educate about what a black hole is. I mean, I can explain it well in English, but to do it in my own language was difficult.

The problem is, we only start learning science in another language. For most of us, English is a second language. And science is, in itself a complex concept and another language. So you're learning English, and while you're still trying to grasp it, you're learning science in English.

If science was taught in Zulu, would it be easier to explain?

You have to create a lexicon of science terms for Zulu, and that takes a lot of researchers and political will, and a lot of funding. But it's happened before. There is a language called Afrikaans, which is a dialect of Dutch, and in South Africa it is a language of science. Three or four decades ago, the government of the time put a lot of effort into making an Afrikaans lexicon of science terms and concepts. We've shown it can happen.

My language can be a language of science, but it's not yet. Not because it's not capable of being so, but because it's not a priority to make it that way.

How did apartheid and colonization impacted South African science?

It's only been 23 years since 1994, just over two decades that South Africa has been democratic. Before that, black people were not allowed to become scientists. We only now have black professors. What this means is that a lot of important science in South Africa, at the highest levels, is done by white men. White people make up a small portion of the population, but they are overrepresented in science.

Today in school, a lot of my peers, including myself, were told that science is not for us. We were told that science is "izinto zabelungu," which means "things of the whites."

But the idea that science is a Western concept is an idea that needs to be removed from people's minds. For that to happen, they need to be taught in their own language.

We've talked about English science concepts that are hard to translate into Zulu. Are there Zulu concepts that are hard to translate into English, that could bring new ways of thinking to science?

I have thought a lot about this, and absolutely. There are many examples where we talk about something in Zulu, and when someone asks you about it in English, it doesn't translate. It's a completely different way of looking at the world.

I learned a lot of astronomy from popular science books, and only later learned that people in my culture used the stars to navigate, tell time and do all sorts of things. A large part of Zulu culture is based on astronomy, the positions of the stars. But I only knew the names of the constellations and planets in English, because there was no effort to teach this in my language. If there was, I would know these things in a much more intimate level, know how these stars, these constellations, were paramount to my ancestors' survival. This would be a part of my knowledge. Astronomy wouldn't be so foreign at all.


To save wine from disease, scientists are breeding native plants

The teaching vineyards at UC Davis.
Photo: Gregory Urquiaga / UC Davis

Pierce's Disease is a grapevine strangler. Once bacteria that cause it get into a plant — via insects — it clogs the plant's vascular system and deprives it of water. There's no treatment. Andy Walker, a plant geneticist at UC Davis, is developing new grape varietals that resist the disease. But once the wine is ready to grow, there's another challenge: getting vintners and consumers to try a new wine.

Why it matters:

  • Modern movement of people seems to have increased the spread of agricultural diseases.
  • It's also possible climate change may increase the range over which a pest or disease can flourish.
  • As demand for organic products increases, Walker thinks vintners will need to grow more disease-resistant types of grapes.

The stigma of genetic modification might be too much for wine consumers. And, Walker says because the genetics for disease resistance are so complicated, it could be hard to engineer a plant that can survive Pierce's Disease. Instead, he bred one.

What they did: North America has a number of native grapes (think: Concord, of Maneschewitz fame), and one of them, the notoriously un-drinkable Vitis arizonica, is resistant to Pierce's Disease. Walker crossed arizonica with traditional European varietals, only selecting offspring that could survive the disease. Each subsequent generation was crossed back with the drinkable grapes.

The challenge: Wine growing comes with deep regional traditions, and consumers love their varietals. Walker says it can be hard for new varietals to gain traction, both with vintners and consumers. "There are over 5,000 different wines, but we only drink a few hundred," Walker notes.

Whit Winslow, the Executive Director of the North Carolina Wine and Grape Council, where Pierce's disease is a problem, tells Axios visitors are eager to try new wines in the tasting room. But he notes that anecdotally, it doesn't necessarily translate to commercial and restaurant sales. "They might walk out of the winery with a new bottle," says Winslow, but that doesn't mean they'll grab one off the liquor-store shelf.

Yes, but: Consumers and vintners can and have been convinced to try new things. In 1996, the Cornell University-developed Traminette wine, which is somewhat fungus and frost resistant, hit the market. A combination of high-profile tasting events and media coverage increased its popularity. Today, it's found in vineyards across the United States, is Indiana's state wine and has won several awards. Bruce Reisch, a plant geneticist at Cornell, helped develop the wine. "No varietal starts with name recognition," says Reisch, but growers are eager to appease consumers' desire for fungicide-free vino.

Looking forward: Walker has only just started doing tastings of the new wines (Reisch has tried them: "they're fantastic!") and they won't be ready for commercial vineyards for a few more years. When they are, it'll likely take some Traminette-style marketing to get consumers ready. But, if Pierce's disease spreads the way some fear it will, Reisch thinks the industry will come together to create a market, and bring a pesticide-free wine to our tables.

Great Salt Lake shrinking may be due to humans' thirst, not climate change

Water levels at the Great Salt Lake have dropped dramatically in the last 170 years

(Credit: johnnya123 / iStock)

The Great Salt Lake is half the size it was in 1847. Scientists previously thought the lake was shrinking due to a shifting climate, but a study published last week in Nature Geoscience says it's getting smaller because humans are using water before it can reach the lake, writes Sarah Derouin for Science Magazine.

Why it matters: The Great Salt Lake is an important refuge for migratory birds and rare aquatic species. As the metropolitan area around the Great Salt Lake grows, the impact on water supply will need to be considered. Study author Wayne Wurtsbaugh tells Derouin water inflows into the lake will need to increase by at least 24% for it to stay healthy. Other salt lakes are shrinking, as well, likely for related reasons.

What they did: The researchers re-created 170 years of climate data using climate records, tree ring data, and stream level records. Precipitation changed little over time but the amount of water flowing into the lake declined greatly.


Coconut crabs also eat birds

A coconut crab kills a red-footed booby. Photo: Mark Laidre / Dartmouth

For decades, scientists believed the nine-pound coconut crab ate, well, coconuts. But in March 2016, biologist Mark Laidre watched one catch, kill and devour a red-footed booby. He described the encounter in a paper published in Frontiers in Ecology last week.

Why it matters: Fairly little is known about coconut crabs, including their diet. Researchers found islands in the Pacific and Indian oceans with lots of the crabs had few ground-nesting birds, and those with lots of birds had no crabs. Since ground-nesting birds are very vulnerable to predators, it's possible voracious coconut crabs influence the distribution of these birds.

  • Coconut crabs are the largest land invertebrates — their legs can span up to a meter across, and they weigh as much as nine pounds. They have the strongest measured grip of any animal.
  • The crabs catch the birds with startling ease, according to Laidre. He watched a crab creep up a tree towards a sleeping bird and pounce, grabbing the bird by the wing and breaking it. The bird fell to the ground unable to fly, and the crab descended, and broke the other wing. Then, it held the bird in place with it's claws, and pummeled it with its legs.
  • The crabs have a keen sense of smell, and soon several others joined in on the feeding frenzy.
  • "It was pretty gruesome, they just converged on the bird and tore it apart," Laidre tells Axios.

Watch it happen: National Geographic, which funded Laidre's expedition, has a video of the crab massacre in action.


How dengue makes the immune system the enemy

Aedes aegypti mosquito. Photo: iStock / Oistock89

When someone gets sick, their body learns what the virus looks like, and destroys it upon re-infection. But when someone is infected with dengue a second time, the immune system appears to help the virus cause a more severe and fatal illness. Previously only seen in the lab, a new study published Thursday in the journal Science shows a direct link between the dengue antibodies themselves and severe illness in humans, supporting a 40-year-old theory.

Why it matters: Dengue fever infects as many as 390 million people each year, up to 96 million of whom will experience symptoms. For most, access to medical treatment makes dengue survivable. But for a small fraction of victims, the virus can progress from a normal infection to a life-threatening hemorrhagic illness in less than a day. A better understanding of how and why this happens could save thousands of lives.

Some background: Dengue is closely related to — and carried by the same mosquitoes as — Zika, chikungunya, and yellow fever. There are four circulating flavors, or serotypes, of dengue. Infection with one type grants immunity to that strain. But a secondary infection with a different dengue virus can lead to dengue hemorrhagic fever or dengue shock syndrome, more severe forms of the disease. Since immune responses make it worse, scientists are concerned about how vaccines and infections from related viruses could influence a dengue infection.

Why it happens: Although scientists agree that a secondary dengue infection is more severe than the first, and that the immune system is involved, the mechanism is debated. The most widely accepted theory is antibody-dependent enhancement, first proposed 40 years ago, which works like this:

  • An individual gets infected with one dengue virus type.
  • They then get infected with a second, different serotype.
  • The immune system recognizes the second dengue enough to respond, but doesn't send the right immune cells to take it down.
  • These antibodies instead inadvertently help the dengue virus enter human immune cells and reproduce more easily.
  • The body then mounts an over-the-top immune response, or cytokine storm. Normally cytokines cause disease-fighting inflammation, but with dengue the response can cause hemorrhage and shock.

Until now it was unknown what level of immune response and immune cells was necessary to trigger this reaction, although tests in the lab suggested there would be a 'sweet spot' for illness.

Past research has suggested that dengue vaccines in people who had never experienced dengue before can increase the risk of severe illness. The World Health Organization recommends the dengue vaccine only be given to children over 9 in areas where diseases levels are high. That means most vaccine recipients will already have some level of immunity.

What they did: The researchers used data from a longitudinal study of over 8,000 Nicaraguan children, 6,600 of whom had antibodies for dengue, and took yearly blood samples. They divided the children into four groups based on the levels of dengue-binding antibodies present in their blood measured via a simple assay. Then, they looked at the future risk of naturally occurring dengue infection developing into dengue hemorrhagic fever or dengue shock syndrome.

What they found: Children with high levels of the antibodies and children who had never had dengue had the same, low risk of developing severe dengue. But children with a specific range of antibodies were 7.64 times more likely to develop severe illness.

There are a few practical implications of this research.

  • Study author Eva Harris imagines, potentially, a future where assays of dengue antibody levels are a normal part of yearly medical exams. If someone becomes re-infected with dengue, they can look at the pre-existing antibody levels and predict the risk of severe dengue developing, and preventatively hospitalize the patient.
  • Past research has shown the dengue vaccine can increase the risk of severe dengue in those who have never been infected. It's possible antibody levels could be used to predict who would benefit most from the expensive vaccines, and who should wait to receive them.

Remaining questions: Research has shown dengue severity can be influenced by which serotypes are circulating, and the order of infection. This study didn't look at the response to specific serotypes only antibody levels. And, while this study has shown a strong predictive correlation between antibody levels and severe dengue, more research is needed before anything definitive can be said.