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September 26, 2018

Study suggests Mars hosted life-sustaining habitat for millions of years

Study suggests Mars hosted life-sustaining habitat for millions of years

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  • 26 September 2018: Study suggests Mars hosted life-sustaining habitat for millions of years
  • 20 September 2018: NASA’s TESS spacecraft reports its first exoplanet
  • 31 July 2018: Total lunar eclipse occurs in July 2018
  • 19 July 2018: US astronomers announce discovering ten tiny Jovian satellites
  • 7 May 2018: NASA’s InSight lander and MarCO craft launch in new mission to Mars

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Wednesday, September 26, 2018

In a new study announced on Monday and available in the current volume of Earth and Planetary Science Letters, an international team led by scientists from Brown University in the United States said the planet Mars once had the right water and temperatures to host simple life forms — just not on its surface. Mars’s rocky, subterranean layer once, for some hundreds of millions of years, had enough water and reductants to support some of the same kinds of microbial communities seen on Earth.

“We showed, based on basic physics and chemistry calculations, that the ancient Martian subsurface likely had enough dissolved hydrogen to power a global subsurface biosphere,” reported lead author and current Brown graduate student Jesse Tarnas. The paper does not claim life on Mars did exist but rather that conditions suitable for life are very likely to have lasted for an extended time. This habitable zone, located beneath Mars’s then-frozen surface, would have reached several kilometers into Mars’s surface, potentially protected by ice above.

The study showed that, during Mars’s Noachian period (4.1–3.7 billion years ago), radiolysis, the process by which radiation splits water molecules apart, produced enough hydrogen gas (H2) for microbial organisms to live on so long as they remained within the area just beneath the cryosphere, the SHZ (subcryospheric highly-fractured zone). The concentration of hydrogen in the groundwater could have ranged from about 35 to about 55 millimolars depending on whether ancient Mars was warm or cold, respectively, and higher if the subsurface medium also contained enough salt. The researchers determined this by establishing three factors. First, they examined data from the gamma ray spectrometer aboard NASA’s Odyssey spacecraft, from which they inferred how much of various radioactive elements would have been present in Mars’s crust during the Noachian, and therefore how much radiation would have been available to split water and so produce hydrogen. They then built on existing models of water flow on Mars to determine how much groundwater would have been present. Third, they used climate and geothermal modeling to determine how much of that water would have been in liquid form and at a suitable temperature for living things.

In subterranean environments on Earth called subsurface lithotrophic microbial ecosystems, or SLiMEs, ecosystems sustain themselves not on plants that harness sunlight through photosynthesis but on microbes that harvest electrons from nearby molecules. Molecular hydrogen is an especially good electron donor.

One of the study authors, Brown Professor John Mustard, is on the team designing the next Mars Rover mission, scheduled for 2020. He and Tarnas recommended the Rover examine the sites of meteorite crashes, which may have excavated rocks from this possibly habitable depth that may hold traces of ancient life.



Related news

  • “NASA’s InSight lander and MarCO craft launch in new mission to Mars” — Wikinews, May 7, 2018
  • “Curiosity Rover analysis suggests chemically complex lake once graced Mars’s Gale crater” — Wikinews, June 4, 2017
  • NASA announces water on Mars” — Wikinews, October 1, 2015

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September 25, 2018

Mars hosted life-sustaining habitat for millions of years, say scientists

Mars hosted life-sustaining habitat for millions of years, say scientists

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  • 20 September 2018: NASA’s TESS spacecraft reports its first exoplanet
  • 31 July 2018: Total lunar eclipse occurs in July 2018
  • 19 July 2018: US astronomers announce discovering ten tiny Jovian satellites
  • 7 May 2018: NASA’s InSight lander and MarCO craft launch in new mission to Mars
  • 21 April 2018: NASA launches exoplanet-hunting satellite TESS

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Tuesday, September 25, 2018

In a new study announced on Monday and available in the current volume of Earth and Planetary Science Letters, an international team led by scientists from Brown University in the United States said the planet Mars once had the right water and temperatures to host simple life forms — just not on its surface. Mars’s rocky, subterranean layer once, for some hundreds of millions of years, had enough water and reductants to support some of the same kinds of microbial communities seen on Earth.

“We showed, based on basic physics and chemistry calculations, that the ancient Martian subsurface likely had enough dissolved hydrogen to power a global subsurface biosphere,” reported lead author and current Brown graduate student Jesse Tarnas. The paper does not claim life on Mars did exist but rather that conditions suitable for life are very likely to have lasted for an extended time. This habitable zone, located beneath Mars’s then-frozen surface, would have reached several kilometers into Mars’s surface, potentially protected by ice above.

The study showed that, during Mars’s Noachian period (4.1–3.7 billion years ago), radiolysis, the process by which radiation splits water molecules apart, produced enough hydrogen gas (H2) for microbial organisms to live on so long as they remained within the area just beneath the cryosphere, the SHZ (subcryospheric highly-fractured zone). The concentration of hydrogen in the groundwater could have ranged from about 35 to about 55 millimolars depending on whether ancient Mars was warm or cold, respectively, and higher if the subsurface medium also contained enough salt. The researchers determined this by establishing three factors. First, they examined data from the gamma ray spectrometer aboard NASA’s Odyssey spacecraft, from which they inferred how much of various radioactive elements would have been present in Mars’s crust during the Noachian, and therefore how much radiation would have been available to split water and so produce hydrogen. They then built on existing models of water flow on Mars to determine how much groundwater would have been present. Third, they used climate and geothermal modeling to determine how much of that water would have been in liquid form and at a suitable temperature for living things.

In subterranean environments on Earth called subsurface lithotrophic microbial ecosystems, or SLiMEs, ecosystems sustain themselves not on plants that harness sunlight through photosynthesis but on microbes that harvest electrons from nearby molecules. Molecular hydrogen is an especially good electron donor.

One of the study authors, Brown Professor John Mustard, is on the team designing the next Mars Rover mission, scheduled for 2020. He and Tarnas recommended the Rover examine the sites of meteorite crashes, which may have excavated rocks from this possibly habitable depth that may hold traces of ancient life.



Related news[]

  • “NASA’s InSight lander and MarCO craft launch in new mission to Mars” — Wikinews, May 7, 2018
  • “Curiosity Rover analysis suggests chemically complex lake once graced Mars’s Gale crater” — Wikinews, June 4, 2017
  • NASA announces water on Mars” — Wikinews, October 1, 2015

Sources[]

This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

September 24, 2018

Mars may once had habitat suitable for subterranean life, say scientists

Mars may once had habitat suitable for subterranean life, say scientists

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  • 20 September 2018: NASA’s TESS spacecraft reports its first exoplanet
  • 31 July 2018: Total lunar eclipse occurs in July 2018
  • 19 July 2018: US astronomers announce discovering ten tiny Jovian satellites
  • 7 May 2018: NASA’s InSight lander and MarCO craft launch in new mission to Mars
  • 21 April 2018: NASA launches exoplanet-hunting satellite TESS

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Monday, September 24, 2018

In a new study available in the current volume of Earth and Planetary Science Letters, a team led by scientists from Brown University in the United States says that the planet Mars once had the right water and temperatures to host simple life forms—just not on its surface. Mars’ rocky, subterranean layer once had enough water and reductants to support some of the same kinds of microbial communities seen on Earth, and this habitat lasted for hundreds of millions of years.

“We showed, based on basic physics and chemistry calculations, that the ancient Martian subsurface likely had enough dissolved hydrogen to power a global subsurface biosphere,” reports lead author Jesse Tarnas, currently a graduate student at Brown. The paper does not prove that life on Mars did exist but rather that conditions suitable for life are very likely to have lasted for eons. This habitable zone, located beneath Mars’ then-frozen surface, would have reached several kilometers into Mars’ surface, protected from freezing by the ice above.

The the study shows that, during Mars’ Noachian period (3.7–4.1 billion years ago), radiolysis, the process by which radiation splits water molecules apart, produced enough hydrogen gas (H2) for microbial organisms to live on so long as they remained within the area just beneath the cryosphere, the SHZ. The concentration of hydrogen in the groundwater could have ranged from about 35 to about 55 millimoles depending on whether ancient Mars was warm or cold, respectively, and higher if the subsurface medium also contained enough salt. The researchers determined this by establishing three factors. First, they examined data from the gamma ray spectrometer aboard NASA’s Odyssey spacecraft, from which they inferred how much uranium would have been present in Mars’ crust during the Noachian, and therefore how much radiation would have been available to split water and so produce hydrogen. Then built on existing models of water flow on Mars to determine how much groundwater would have been present. Third, they used climate and geothermal modeling to determine how much of that water would have been in liquid form and at a suitable temperature for living things.

In subterranean environments on Earth called subsurface lithotrophic microbial ecosystems, or SLiMEs, ecosystems sustain themselves not on plants that harness sunlight through photosynthesis but on microbes that harvest electrons from nearby molecules. Molecular hydrogen is an especially good electron donor.

One of the study authors, Brown Professor John Mustard, is on the team designing the next Mars Rover mission, scheduled for 2020. He and his co-authors recommend that the Rover examine the sites of meteorite crashes, which may have excavated rocks from this possibly habitable depth that may hold traces of ancient life.



Related news[]

  • “NASA’s InSight lander and MarCO craft launch in new mission to Mars” — Wikinews, May 7, 2018
  • “Curiosity Rover analysis suggests chemically complex lake once graced Mars’s Gale crater” — Wikinews, June 4, 2017
  • NASA announces water on Mars” — Wikinews, October 1, 2015

Sources[]

This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

Mars hosted a life-sustaining habitat for millions of years, say scientists

Mars hosted a life-sustaining habitat for millions of years, say scientists

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  • 20 September 2018: NASA’s TESS spacecraft reports its first exoplanet
  • 31 July 2018: Total lunar eclipse occurs in July 2018
  • 19 July 2018: US astronomers announce discovering ten tiny Jovian satellites
  • 7 May 2018: NASA’s InSight lander and MarCO craft launch in new mission to Mars
  • 21 April 2018: NASA launches exoplanet-hunting satellite TESS

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Monday, September 24, 2018

In a new study available in the current volume of Earth and Planetary Science Letters, a team led by scientists from Brown University in the United States says the planet Mars once had the right water and temperatures to host simple life forms—just not on its surface. Mars’ rocky, subterranean layer once had enough water and reductants to support some of the same kinds of microbial communities seen on Earth, and this habitat lasted for hundreds of millions of years.

“We showed, based on basic physics and chemistry calculations, that the ancient Martian subsurface likely had enough dissolved hydrogen to power a global subsurface biosphere,” reports lead author Jesse Tarnas, currently a graduate student at Brown. The paper does not prove life on Mars did exist but rather that conditions suitable for life are very likely to have lasted for eons. This habitable zone, located beneath Mars’ then-frozen surface, would have reached several kilometers into Mars’ surface, protected from freezing by the ice above.

The the study shows that, during Mars’ Noachian period (3.7–4.1 billion years ago), radiolysis, the process by which radiation splits water molecules apart, produced enough hydrogen gas (H2) for microbial organisms to live on so long as they remained within the area just beneath the cryosphere, the SHZ. The concentration of hydrogen in the groundwater could have ranged from about 35 to about 55 millimoles depending on whether ancient Mars was warm or cold, respectively, and higher if the subsurface medium also contained enough salt. The researchers determined this by establishing three factors. First, they examined data from the gamma ray spectrometer aboard NASA’s Odyssey spacecraft, from which they inferred how much uranium would have been present in Mars’ crust during the Noachian, and therefore how much radiation would have been available to split water and so produce hydrogen. They then built on existing models of water flow on Mars to determine how much groundwater would have been present. Third, they used climate and geothermal modeling to determine how much of that water would have been in liquid form and at a suitable temperature for living things.

In subterranean environments on Earth called subsurface lithotrophic microbial ecosystems, or SLiMEs, ecosystems sustain themselves not on plants that harness sunlight through photosynthesis but on microbes that harvest electrons from nearby molecules. Molecular hydrogen is an especially good electron donor.

One of the study authors, Brown Professor John Mustard, is on the team designing the next Mars Rover mission, scheduled for 2020. He and his co-authors recommend the Rover examine the sites of meteorite crashes, which may have excavated rocks from this possibly habitable depth that may hold traces of ancient life.



Related news[]

  • “NASA’s InSight lander and MarCO craft launch in new mission to Mars” — Wikinews, May 7, 2018
  • “Curiosity Rover analysis suggests chemically complex lake once graced Mars’s Gale crater” — Wikinews, June 4, 2017
  • NASA announces water on Mars” — Wikinews, October 1, 2015

Sources[]

This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

August 25, 2018

Fossil genome shows hybrid of two extinct species of human

Fossil genome shows hybrid of two extinct species of human

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Saturday, August 25, 2018

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A team of scientists has announced remains of a human girl from about 50 thousand years ago had one Neanderthal parent and one Denisovan parent, two different species of humans, both species now extinct. The results, from genomic tests in Leipzig, Germany of fossil bone from Siberia, Russia, were published on Wednesday in scientific journal Nature. The researchers said this is the first discovery of a child with parents of different human species.

The single fossilized bone fragment, about two centimetres (less than an inch) long, which researchers said was from a girl at least 13 years old, was found in 2012 in the Denisova Cave in Siberia. The Denisovan species of humans is only directly known from the same cave, where it was discovered in 2011; the cave is also the only site where both Nenderthal and Denisovan remains have been found. Neanderthals have been found in Europe and Asia. Traces of genes from both species occur in some modern humans. Researchers found the nuclear DNA in this bone fragment was split fairly evenly between both species, while the mitochondrial DNA was Neanderthal; nuclear DNA comes from both parents, while mitochondrial DNA comes only from the mother, so they concluded the girl’s mother was Neanderthal and her father Denisovan.

Lead author on the study Viviane Slon, of the Max Planck Institute for Evolutionary Anthropology (MPI-EVA) in Leipzig, said “We knew from previous studies that Neanderthals and Denisovans must have occasionally had children together […] But I never thought we would be so lucky as to find an actual offspring of the two groups.” The team rechecked the findings several times. Scientist Johannes Krause, of the Max Planck Institute for the Science of Human History in Jena, called the finding “sensational”. Study coauthor Svante Pääbo, of MPI-EVA, remarked on the improbability of discovering such a hybrid when only two dozen human genomes over 40 thousand years old —when the other species of humans were still around— have been done: “The fact that we stumbled across this makes you wonder if the mixing wasn’t quite frequent […] Had it happened frequently, we would not have such divergence between the Denisovans and Neanderthal genomes.”

The researchers also noted the girl’s father, though Denisovan, had a trace of Neanderthal DNA, from perhaps as much as several hundred generations earlier. They also reported the mother’s DNA was not closely related to that of other Neanderthals found in the cave, suggesting multiple migrations of Neanderthals between Siberia and Europe.



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  • Viviane Slon, Fabrizio Mafessoni, Benjamin Vernot, Cesare de Filippo, Steffi Grote, Bence Viola, Mateja Hajdinjak, Stéphane Peyrégne, Sarah Nagel, Samantha Brown, Katerina Douka, Tom Higham, Maxim B. Kozlikin, Michael V. Shunkov, Anatoly P. Derevianko, Janet Kelso, Matthias Meyer, Kay Prüfer, Svante Pääbo. “The genome of the offspring of a Neanderthal mother and a Denisovan father” — Nature (journal), August 22, 2018
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October 8, 2015

The Nobel Prize in Chemistry 2015 shared by 3 scientists for how damaged DNA is repaired

The Nobel Prize in Chemistry 2015 shared by 3 scientists for how damaged DNA is repaired

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Thursday, October 8, 2015

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Yesterday, the Royal Swedish Academy of Sciences awarded the Nobel Prize in Chemistry to three scientists for their work on DNA repair. Tomas Lindahl, Paul Modrich and Aziz Sancar showed how damaged DNA is repaired and genetic information is safeguarded by the cells at the molecular level. Their collaborative studies have contributed to knowledge behind the functioning of a cell.

Swedish scientist Tomas Lindahl found that DNA molecules decay at a significant rate, which evolution could have not sustained. This led to the discovery of base excision repair, a cellular mechanism that repairs the damaged DNA.



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Three scientists share 2015 Chemistry Nobel Prize for DNA repair research

Three scientists share 2015 Chemistry Nobel Prize for DNA repair research

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Thursday, October 8, 2015

Artist’s rendition of damaged DNA being repaired.
Image: Tom Ellenberger.

Yesterday, Göran K. Hansson, permanent secretary of the Royal Swedish Academy of Sciences, announced this year’s Nobel Prize in Chemistry is awarded to three scientists for their work on DNA repair.

Tomas Lindahl, Paul Modrich and Aziz Sancar showed how damaged DNA is repaired and genetic information is safeguarded by the cells at the molecular level.

Swedish scientist Tomas Lindahl found that DNA molecules decay too quickly for life, or evolution, to be sustainable. This led to the discovery of base excision repair, a cellular mechanism that repairs damaged DNA by removing erroneous sections and replacing them.

Turkish molecular biologist Aziz Sancar mapped nucleotide excision repair, a DNA repair mechanism that targets larger-scale damage caused by mutagens and ultraviolet radiation.

US professor of biochemistry Paul Modrich showed how errors caused during DNA replication are usually rectified. DNA mismatch repair increases the precision of DNA replication when cells divide.

The prize is shared 1/3rd to each scientist.


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  • “2006 Nobel Prize in chemistry for insight into cells” — Wikinews, October 4, 2006

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September 3, 2015

Study estimates Earth has over three trillion trees

Study estimates Earth has over three trillion trees

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Thursday, September 3, 2015

A study published yesterday by Nature estimates the global tree population at just over three trillion. Previous work estimated the total at 400 billion.

A young tree in Saudi Arabia
Image: Francisco Anzola.

The international research, led by Yale University in the US, used satellite images to examine over 400,000 plots of land for estimated tree density. Subarctic regions of Scandinavia, Russia, and North America had the highest densities but the largest forested areas were tropical. The study puts 43% of trees in the tropics, where deforestation is particularly common.

The study also claims the number has been cut by human activity from around six trillion 12,000 years ago. Lead researcher Thomas Crowther said “We have nearly halved the number of trees on the planet, and we have seen the impacts on climate and human health as a result. This study highlights how much more effort is needed if we are to restore healthy forests worldwide.” Crowther was “surprised” to come up with a number as high as the trillions.

The study was made at the request of a United Nations project which wanted an estimate on which to base reforestation targets. As well as numbers and distribution the study looks at what factors might control the density of trees in any given area, such as soil type. The study suggests trees outnumber humans by around 422 to one.

“It’s not like we’ve discovered a load of new trees; it’s not like we’ve discovered a load of new carbon”, cautioned Crowther, speaking to the BBC. “So, it’s not good news for the world or bad news that we’ve produced this new number.” He says the estimate is valuable for lawmakers, academics, and the general public.



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September 1, 2015

Biologist Nick Bos tells Wikinews about \’self-medicating\’ ants

Biologist Nick Bos tells Wikinews about ‘self-medicating’ ants

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Tuesday, September 1, 2015

Formica fusca, from file.
Image: Mathias Krumbholz.

Nick Bos, of the University of Helsinki, studies “the amazing adaptations social insects have evolved in order to fight the extreme parasite pressure they experience”. In a recently-accepted Evolution paper Bos and colleagues describe ants appearing to self-medicate.

Cquote1.svg I have no doubt that as time goes on, there will be more and more cases documented Cquote2.svg

The team used Formica fusca, an ant species that can form thousand-strong colonies. This common black ant eats other insects, and also aphid honeydew. It often nests in tree stumps or under rocks and foraging workers can sometimes be spotted climbing trees.

Some ants were infected with Beauveria bassiana, a fungus. Infected ants chose food laced with toxic hydrogen peroxide, whereas healthy ants avoided it. Hydrogen peroxide reduced infected ant fatalities by 15%, and the ants varied their intake depending upon how high the peroxide concentration was.

In the wild, Formica fusca can encounter similar chemicals in aphids and dead ants. The Independent reported self-medicating ants a first among insects.

Bos obtained his doctorate from the University of Copenhagen. He began postdoctoral research at Helsinki in 2012. He also runs the AntyScience blog. The blog aims to help address “a gap between scientists and ‘the general public’.” The name is a pun referencing ants, its primary topic, science, and “non-scientific” jargon-free communication. He now discusses his work with Wikinews.

Beauveria bassiana on a cicada in Bolivia.
Image: Danny Newman.

Wikinews waves Left.pngWikinewsWikinews waves Right.png What first attracted you to researching ants?

Nick Bos Me and a studymate were keeping a lot of animals during our studies, from beetles, to butterflies and mantids, to ants. We had the ants in an observation nest, and I could just look at them for hours, watching them go about. This was in my third year of Biology study I think. After a while I needed to start thinking about an internship for my M.Sc. studies, and decided to write a couple of professors. I ended up going to the Centre for Social Evolution at the University of Copenhagen where I did a project on learning in Ants under supervision of Prof. Patrizia d’Ettorre. I liked it so much there I ended up doing a PhD and I’ve been working on social insects ever since.

Wikinews waves Left.pngWikinewsWikinews waves Right.png What methods and equipment were used for this investigation?

NB This is a fun one. I try to work on a very low budget, and like to build most of the experimental setups myself (we actually have equipment in the lab nicknamed the ‘Nickinator’, ‘i-Nick’ and the ‘Nicktendo64’). There’s not that much money in fundamental science at the moment, so I try to cut the costs wherever possible. We collected wild colonies of Formica fusca by searching through old tree-trunks in old logging sites in southern Finland. We then housed the ants in nests I made using Y-tong [aerated concrete]. It’s very soft stone that you can easily carve. We carved out little squares for the ants to live in (covered with old CD covers to prevent them escaping!). We then drilled a tunnel to a pot (the foraging arena), where the ants got the choice between the food with medicine and the food without.
We infected the ants by preparing a solution of the fungus Beauveria bassiana. Afterwards, each ant was dipped in the solution for a couple of seconds, dried on a cloth and put in the nest. After exposing the ants to the fungus, we took pictures of each foraging arena three times per day, and counted how many ants were present on each food-source.

Example of aerated concrete, which provided a home for the subjects.
Image: Marco Bernardini.

This gave us the data that ants choose more medicine after they have been infected.
The result that healthy ants die sooner when ingesting ROS [Reactive Oxygen Species, the group of chemicals that includes hydrogen peroxide] but infected ants die less was obtained in another way (as you have to ‘force feed’ the ROS, as healthy ants, when given the choice, ignore that food-source.)
For this we basically put colonies on a diet of either food with medicine or without for a while. And afterwards either infected them or not. Then for about two weeks we count every day how many ants died. This gives us the data to do a so-called survival analysis.
We measured the ROS-concentration in the bodies of ants after they ingested the food with the medicine using a spectrophotometer. By adding certain chemicals, the ROS can be measured using the emission of light of a certain wave-length.
The detrimental effect of ROS on spores was easy to measure. We mixed different concentrations of ROS with the spores, plated them out on petridishes with an agar-solution where fungus can grow on. A day after, we counted how many spores were still alive.

Wikinews waves Left.pngWikinewsWikinews waves Right.png How reliable do you consider your results to be?

NB The results we got are very reliable. We had a lot of colonies containing a lot of ants, and wherever possible we conducted the experiment blind. This means the experimenter doesn’t know which ants belong to which treatment, so it’s impossible to influence the results with ‘observer bias‘. However, of course this is proof in just one species. It is hard to extrapolate to other ants, as different species lead very different lives.
Cquote1.svg At the moment it seems that sick ants mostly take care of the problem themselves Cquote2.svg

Wikinews waves Left.pngWikinewsWikinews waves Right.png Where did the ants and fungus you used come from? How common are they in the wild?

NB For ants, see above about the collection.
This species of fungus does appear in Finland, but we chose to use a different strain from Denmark (with thanks to Prof. J. Eilenberg and the laboratory technician Louise Lee Munch Larsen from the University of Copenhagen). Animals can adapt to local strains (‘local adaptation’), and just to make sure we thought it would be good to use a strain of fungus that the ants definitely did not evolve specific resistances against. This means that the reaction of the ants (to self-medicate) is very likely to be a general response, and not just against their local fungal enemies.

The Univeristy of Helsinki from file.
Image: Smaug.

Wikinews waves Left.pngWikinewsWikinews waves Right.png Are there any ethical considerations around exposing ants to toxins and parasites?

NB Legally, no. Insects do not have any ‘rights’ as such regarding ethics. That said, we do take measures to not make them ‘suffer unnecessarily’. For example, dissections are done when the ants are anesthetized (either by CO2 or Ice), and when ants need to be killed, we do it in alcohol, which kills the ants in a matter of seconds. So while the ants do not have ‘rights’ as such, we still try to handle them with as much respect as possible (even though the experiment involves infecting them with a deadly fungus).
But even though the 12,000 ants in our study sounds like a lot (and it is), this is negligible in the ‘grand scheme of things’. It has been calculated that in the Netherlands alone, nearly a trillion insects die against just the licence-plates of cars every six months. I don’t own a car, so that means I’m excused right? 😉

Wikinews waves Left.pngWikinewsWikinews waves Right.png This is the first evidence for self-medicating insects. How widespread do you think this phenomenon could be in reality?

NB It’s not actually the first evidence for self-medication in insects. Moths and fruit flies definitely do it, and there’s evidence in honey bees and bumble-bees as well. So it seems to be quite wide-spread in the insect world. I have no doubt that as time goes on, there will be more and more cases documented. Insects (and animals in general) seem to be quite good at taking care of themselves.

Wikinews waves Left.pngWikinewsWikinews waves Right.png How might ants locate healing substances in the wild?

NB Very good question. This is something that’s important to know. If they would only do it in the lab, the behaviour wouldn’t be very interesting. We have some guesses where they might get it from, but at the moment we don’t know yet. That said, I plan to investigate this question (among others) further [in] the next couple of years.

Another file photo of Formica fusca, this time showing foraging workers feeding.
Image: Sedeer El-Showk.

Wikinews waves Left.pngWikinewsWikinews waves Right.png For your PhD you researched ants’ scent-based communications. Could healthy ants perhaps tell other ants are infected and encourage this behaviour?

NB There’s not much known about this. There’s conflicting evidence about whether sick ants actually smell different from healthy ones or not. At the moment it seems that sick ants mostly take care of the problem themselves. Sick ants stop most interaction with nestmates and especially brood, and leave the nest to die in isolation. This is probably for reducing chance of infecting nestmates, but of course it also reduces the work load of their nest-mates, as their corpse doesn’t have to be dragged out etc.
So as an answer to the question, I would find it unlikely that such a behaviour would evolve, but it’s not known yet.

Wikinews waves Left.pngWikinewsWikinews waves Right.png Ants generally avoided the peroxide if they were healthy, but in some circumstances might they try to build resistance against infection in advance?

NB Who knows? Also not known yet unfortunately. That said, there is a very interesting study about resin collection in ants. Wood ants collect tree-resin, which has anti-microbial properties. They collect this even if not infected, and when you infect them, they don’t collect more of the resin than normal. So basically it seems like they collect it in order to keep diseases out of the nest, so they stop the disease before it can actually infect them.

Wikinews waves Left.pngWikinewsWikinews waves Right.png Are there plans to follow this research up? Might you research other species? Other substances?

NB I first want to find out where they get it from in nature. There might be many sources of medicine (recent evidence suggests that tobacco plays a similar role for bumble bees). Dalial Freitak, who is also on this paper is currently running tests with Ph.D. student Siiri Fuchs (who is also on the paper) with other substances to see if any have the same effect as H2O2 [hydrogen peroxide].
Once the behaviour has been well described in this species of ant, I might do a comparison with other species. For example, once we find the source of the medicine in nature… would species without access to this source also have evolved the same behaviour in the lab? And if so… where would they get it from?
Also… can ants medicate their friends? 🙂

Wikinews waves Left.pngWikinewsWikinews waves Right.png What other research are you working on right now?

NB Phew…lots! 🙂
I still have some questions left unanswered from my Ph.D. work related to how ants recognize who is a friend and who isn’t. I also started collaborating with Prof. Michael Poulsen from the University of Copenhagen on immunity in fungus-growing termites, as well as their chemical recognition abilities. Furthermore we’re working on social parasitism in wood-ants (ants have lots of animals exploiting the nest for shelter and resources, which all somehow have to get in to the fortress without getting killed).



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January 31, 2015

Rare megamouth shark found dead in Pio Duran, Philippines

Rare megamouth shark found dead in Pio Duran, Philippines

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Saturday, January 31, 2015

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A megamouth shark was found dead in the Philippines on Wednesday. There have been only fifteen confirmed sightings in the nation and around 60 worldwide.

Preserved head of a megamouth on display in Australia.
Image: “saberwyn”.

The fifteen-foot male was found after reportedly becoming entangled with a fishing net near the Barangay Marigondon neighborhood of Pio Duran, Albay province. Its body was encased with ice pending a necropsy. The cause of death was not immediately clear.

Locals have nicknamed the dead shark ‘toothless’, a How to Train Your Dragon movie reference. In truth megamouths can have up to fifty rows of teeth.

Megamouths reach up to eighteen feet. Their name refers to its large head and mouth, used to filter plankton and other small food from the ocean. Occasionally the prey of other sharks and whales, megamouths are thought to live in the Pacific around Taiwan, the Philippines, and Japan based on previous sightings. Its true range and population size are however unknown. The first such shark identified was accidentally discovered by the US Navy off the coast of Hawaii when it became stuck in a ship’s anchor. Researchers theorise a white strip on the shark’s head illuminates to attract prey.



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