Category: Environment

{The potential evolutionary link between hairs in mammals, feathers in birds and scales in reptiles has been debated for decades. Today, researchers of the University of Geneva (UNIGE) and the SIB Swiss Institute of Bioinformatics, Switzerland, demonstrate that all these skin appendages are homologous: they share a common ancestry. On the basis of new analyses of embryonic development, the Swiss biologists evidenced molecular and micro-anatomical signatures that are identical between hairs, feathers and scales at their early developmental stages. These new observations, published in Science Advances, indicate that the three structures evolved from their common reptilian ancestor.}

Mammalian hairs and avian feathers develop from a similar primordial structure called a ‘placode’: a local thickening of the epidermis with columnar cells that reduce their rate of proliferation and express very specific genes. This observation has puzzled evolutionary and developmental biologists for many years because birds and mammals are not sister groups: they evolved from different reptilian lineages. According to previous studies, reptiles’ scales however do not develop from an anatomical placode. This would imply that birds and mammals have independently ‘invented’ placodes during their evolution.

{{The single evolutionary origin of placodes revealed}}

In 2015, a team from Yale University (USA) published an article showing that scales, hairs and feathers share molecular signatures during their development. These results fueled an old debate between two schools. One defends that these molecular signatures suggest a common evolutionary origin of skin appendages, whereas the other proposes that the same genes are re-used for developing different skin appendages.

Today, Nicolas Di-Poï and Michel C. Milinkovitch at the Department of Genetics and Evolution of the UNIGE Faculty of Science and at the SIB put this long controversy to rest by demonstrating that scales in reptiles develop from a placode with all the anatomical and molecular signatures of avian and mammalian placodes. The two scientists finely observed and analysed the skin morphological and molecular characteristics during embryonic development in crocodiles, snakes and lizards. ‘Our study not only provides new molecular data that complement the work of the American team but also reveals key microanatomical facts, explains Michel Milinkovitch. Indeed, we have identified in reptiles new molecular signatures that are identical to those observed during the development of hairs and feathers, as well as the presence of the same anatomical placode as in mammals and birds. This indicates that the three types of skin appendages are homologous: the reptilian scales, the avian feathers and the mammalian hairs, despite their very different final shapes, evolved from the scales of their reptilian common ancestor.’

{{A key gene for skin appendage development}}

During their new study, the researchers from UNIGE and SIB also investigated the bearded dragon, a species of lizard that comes in three variants. The first is the normal wild-type form. The second has scales of reduced size because it bears one copy of a natural genetic mutation. The third has two copies of the mutation … and lacks all scales. By comparing the genome of these three variants, Di-Poï and Milinkovitch have discovered the gene affected by this mutation. ‘We identified that the peculiar look of these naked lizards is due to the disruption of the ectodysplasin-A (EDA), a gene whose mutations in humans and mice are known to generate substantial abnormalities in the development of teeth, glands, nails and hairs’, says Michel Milinkovitch. The Swiss researchers have demonstrated that, when EDA is malfunctioning in lizards, they fail to develop a proper scale placode, exactly as mammals or birds affected with similar mutations in that same gene cannot develop proper hairs or feathers placodes. These data all coherently indicate the common ancestry between scales, feathers and hairs.

The next challenge for the Swiss team, and many other researchers around the world, is to decipher the fine mechanisms explaining the diversity of forms of skin appendages. How has the ancestral scaly skin given rise to the very different morphologies of scales, feathers and hairs, as well as the astonishing variety of forms that these appendages can take? These future studies will hopefully fine-tune our understanding of the physical and molecular mechanisms generating the complexity and the diversity of life during evolution.

{An international team of scientists have found a potentially viable way to remove anthropogenic (caused or influenced by humans) carbon dioxide emissions from the atmosphere — turn it into rock.}

The study, published in Science, has shown for the first time that the greenhouse gas carbon dioxide (CO2) can be permanently and rapidly locked away from the atmosphere, by injecting it into volcanic bedrock. The CO2 reacts with the surrounding rock, forming environmentally benign minerals.

Measures to tackle the problem of increasing greenhouse gas emissions and resultant climate change are numerous. One approach is Carbon Capture and Storage (CCS), where CO2 is physically removed from the atmosphere and trapped underground. Geoengineers have long explored the possibility of sealing CO2 gas in voids underground, such as in abandoned oil and gas reservoirs, but these are susceptible to leakage. So attention has now turned to the mineralisation of carbon to permanently dispose of CO2.

Until now it was thought that this process would take several hundreds to thousands of years and is therefore not a practical option. But the current study — led by Columbia University, University of Iceland, University of Toulouse and Reykjavik Energy — has demonstrated that it can take as little as two years.

Lead author Dr Juerg Matter, Associate Professor in Geoengineering at the University of Southampton, says: “Our results show that between 95 and 98 per cent of the injected CO2 was mineralised over the period of less than two years, which is amazingly fast.”

The gas was injected into a deep well at the study site in Iceland. As a volcanic island, Iceland is made up of 90 per cent basalt, a rock rich in elements such as calcium, magnesium and iron that are required for carbon mineralisation. The CO2 is dissolved in water and carried down the well. On contact with the target storage rocks, at 400-800 metres under the ground, the solution quickly reacts with the surrounding basaltic rock, forming carbonate minerals.

“Carbonate minerals do not leak out of the ground, thus our newly developed method results in permanent and environmentally friendly storage of CO2 emissions,” says Dr Matter, who is also a member of the University’s Southampton Marine and Maritime Institute and Adjunct Senior Scientist at Lamont-Doherty Earth Observatory Columbia University. “On the other hand, basalt is one of the most common rock type on Earth, potentially providing one of the largest CO2 storage capacity.”

To monitor what was happening underground, the team also injected ‘tracers’, chemical compounds that literally trace the transport path and reactivity of the CO2. There were eight monitoring wells at the study site, where they could test how the chemical composition of the water had changed. The researchers discovered that by the time the groundwater had migrated to the monitoring wells, the concentration of the tracers — and therefore the CO2 — had diminished, indicating that mineralisation had occurred.

“Storing CO2 as carbonate minerals significantly enhances storage security which should improve public acceptance of Carbon Capture and Storage as a climate change mitigation technology,” says Dr Matter.

“The overall scale of our study was relatively small. So, the obvious next step for CarbFix is to upscale CO2 storage in basalt. This is currently happening at Reykjavik Energy’s Hellisheidi geothermal power plant, where up to 5,000 tonnes of CO2 per year are captured and stored in a basaltic reservoir.”

The investigation is part of the CarbFix project, a European Commission and U.S. Department of Energy funded programme to develop ways to store anthropogenic CO2 in basaltic rocks through field, laboratory and modelling studies (http://carbfix.com).

{A species of tropical fish has been shown to be able to distinguish between human faces. It is the first time fish have demonstrated this ability.}

The research, carried out by a team of scientists from the University of Oxford (UK) and the University of Queensland (Australia), found that archerfish were able to learn and recognize faces with a high degree of accuracy — an impressive feat, given this task requires sophisticated visual recognition capabilities.

The study is published in the journal Scientific Reports.

First author Dr Cait Newport, Marie Curie Research Fellow in the Department of Zoology at Oxford University, said: ‘Being able to distinguish between a large number of human faces is a surprisingly difficult task, mainly due to the fact that all human faces share the same basic features. All faces have two eyes above a nose and mouth, therefore to tell people apart we must be able to identify subtle differences in their features. If you consider the similarities in appearance between some family members, this task can be very difficult indeed.

‘It has been hypothesized that this task is so difficult that it can only be accomplished by primates, which have a large and complex brain. The fact that the human brain has a specialized region used for recognizing human faces suggests that there may be something special about faces themselves. To test this idea, we wanted to determine if another animal with a smaller and simpler brain, and with no evolutionary need to recognize human faces, was still able to do so.’

The researchers found that fish, which lack the sophisticated visual cortex of primates, are nevertheless capable of discriminating one face from up to 44 new faces. The research provides evidence that fish (vertebrates lacking a major part of the brain called the neocortex) have impressive visual discrimination abilities.

In the study, archerfish — a species of tropical fish well known for its ability to spit jets of water to knock down aerial prey — were presented with two images of human faces and trained to choose one of them using their jets. The fish were then presented with the learned face and a series of new faces and were able to correctly choose the face they had initially learned to recognize. They were able to do this task even when more obvious features, such as head shape and colour, were removed from the images.

The fish were highly accurate when selecting the correct face, reaching an average peak performance of 81% in the first experiment (picking the previously learned face from 44 new faces) and 86% in second experiment (in which facial features such as brightness and colour were standardized).

Dr Newport said: ‘Fish have a simpler brain than humans and entirely lack the section of the brain that humans use for recognizing faces. Despite this, many fish demonstrate impressive visual behaviours and therefore make the perfect subjects to test whether simple brains can complete complicated tasks.

‘Archerfish are a species of tropical freshwater fish that spit a jet of water from their mouth to knock down insects in branches above the water. We positioned a computer monitor that showed images of human faces above the aquariums and trained them to spit at a particular face. Once the fish had learned to recognize a face, we then showed them the same face, as well as a series of new ones.

‘In all cases, the fish continued to spit at the face they had been trained to recognize, proving that they were capable of telling the two apart. Even when we did this with faces that were potentially more difficult because they were in black and white and the head shape was standardized, the fish were still capable of finding the face they were trained to recognize.

‘The fact that archerfish can learn this task suggests that complicated brains are not necessarily needed to recognize human faces. Humans may have special facial recognition brain structures so that they can process a large number of faces very quickly or under a wide range of viewing conditions.’

Human facial recognition has previously been demonstrated in birds. However, unlike fish, they are now known to possess neocortex-like structures. Additionally, fish are unlikely to have evolved the ability to distinguish between human faces.

{The shiny reptile likely numbers only a thousand individuals in its remote Bahamas habitat, experts say.}

On an uninhabited island in the southern Bahamas, a scientist noticed a snake that shined like metal as it climbed a tree.

“We all came to take a look at it, and it was instantly clear that this was something different,” says biologist R. Graham Reynolds, part of the scientific team exploring the remote islands.

Expedition member Alberto Puente-Rolón, an expert on Caribbean boas, agreed that the animal appeared unlike any species of known boa.

So the team went searching for more boas, finding four more snakes before settling down to sleep on the beach at Conception Island. But it turns out the boas weren’t ready to call it a night. (See “Extremely Rare Fishing Snakes Discovered.”)

“Sometime around 3:30 in the morning, I woke up to something crawling across my face,” says Reynolds, now a biologist at the University of North Carolina, Asheville.

Another silver boa had come down from the forest and crawled right over him as he slept. They’d located their sixth specimen, and DNA analyses back at the lab confirmed the snake was a new species.

The scientists named the Conception Bank silver boa (Chilabothrus argentum), based on both its color and the fact it was first found on an aptly named silver palm tree. A study on the species appeared in the journal Breviora.

“This discovery is significant because of how well-studied many parts of the Bahamas are, especially in terms of herpetology,” says Julie Ray, director of the conservation group Team Snake Panama.

{{On the Edge}}

The three other Bahamian boa species look different from the newfound species, with dark splotches and stripes. The silver boa is not only paler, it also—unlike the others—lives in trees, where it feeds mostly on birds.

“This new species occurs on a group of islands that have never been connected to any of the other islands in the Bahamas,” says Reynolds. “As far as we know, they only occur on Conception Island Bank and nowhere else.” (See “Why We Were Totally Wrong About How Boa Constrictors Kill.”)

Thus, the entire silver boa population, which the team estimates to be fewer than a thousand animals, is found only in one small patch of Earth.

If You’re Scared of Snakes, Don’t Watch This Every year, thousands of snakes gather at the Narcisse Snake Dens in Manitoba, Canada.
This makes the species vulnerable to extinction, and Reynolds and his colleagues believe the silver boa should be designated as critically endangered by the International Union for Conservation of Nature.

{{Silver Lining?}}

Fortunately for the silver boa, all islands on the Conception Island Bank are national parkland, and visitors to the area are relatively rare.

Reynolds and his colleagues are working with the Bahamas National Trust, which administers the national parks, on strategies to protect the species.

The reptile faces threats such as natural disasters (which could wipe out the entire population); poaching for the pet trade; and feral cats, which exist on Conception Island and are known to prey on boas elsewhere in the Bahamas.

Ray agrees that despite living in a refuge, the boa is still in danger—in particular from feral cats and dogs.

“All efforts should be made to restrict the number of dogs on the island and how freely they are allowed to roam,” says Ray.

“More importantly, an attempt should be made to remove the feral cats from this protected natural area because they are not native predators.”

{A hominin in the same genus as humans and an ape nicknamed “Laia” that might provide clues to the origin of humans are among the discoveries identified by the SUNY College of Environmental Science and Forestry (ESF) as the Top 10 New Species for 2016.}

The list also includes a new kind of giant Galapagos tortoise, which could serve as a poster species for conservation and evolution, and two fish — a seadragon in stunning shades of ruby red and pink and, conversely, an anglerfish that would not win an undersea beauty pageant.

Rounding out this year’s Top 10 are three invertebrates — a tiny isopod that builds its own mud shelters, a beetle named after a fictional bear who traveled from Peru to London and a damselfly with a suggestive name, and two plants — a carnivorous sundew that was considered endangered as soon as it was found and a tree that was hiding in plain sight.

Brazil and Gabon each contributed two new additions to the planet’s biodiversity. The others hail from Ecuador, South Africa, the Gulf of Mexico, Australia, Spain and Peru.

The list is compiled annually by ESF’s International Institute for Species Exploration (IISE). The institute’s international committee of taxonomists selects the Top 10 from among the approximately 18,000 new species named during the previous year. The list is made public around May 23 to recognize the birthday of Carolus Linnaeus, an 18th century Swedish botanist who is considered the father of modern taxonomy.

Established in 2008, the list calls attention to discoveries that are made even as species are going extinct faster than they are being identified. “In the past half-century we have come to recognize that species are going extinct at an alarming rate. It is time that we accelerate species exploration, too. Knowledge of what species exist, where they live, and what they do will help mitigate the biodiversity crisis and archive evidence of the life on our planet that does disappear in the wild,” said Dr. Quentin Wheeler, ESF president and founding director of the IISE.

Scientists believe 10 million species await discovery, five times the number that are already known to science.

“The rate of description of species is effectively unchanged since before World War II. The result is that species are disappearing at a rate at least equal to that of their discovery. We can only win this race to explore biodiversity if we pick up the pace. In so doing we gather irreplaceable evidence of our origins, discover clues to more efficient and sustainable ways to meet human needs, and arm ourselves with fundamental knowledge essential for wide-scale conservation success,” Wheeler said.

{{The 2016 Top 10 New Species

Giant Tortoise: 185 Years Post-Darwin, a New Species in Galapagos

Chelonoidis donfaustoi

Location: Galapagos, Ecuador
}}

How it made the Top 10: No animals are more immediately associated with evolution or Charles Darwin than the giant tortoises of the Galapagos. Small differences had been noticed between eastern and western populations of giant tortoises on Santa Cruz Island that were assumed to be simply genetic variation within the known species, C. porteri. A careful analysis of both genetic and morphological data, however, shows that the smaller eastern population, with perhaps as few as 250 individuals, is a distinct and new species. This discovery has immediate, important conservation implications. C. porteri has a more limited geographic range than previously believed, restricted to western and southwestern areas of the island, and care must be taken to avoid bridging the natural isolation of the two species. The new species was named in honor of a park ranger known as “Don Fausto,” who worked 43 years to conserve the giant tortoises of Galapagos.

{{Giant Sundew: Carnivorous Plant Debuts on Social Media

Drosera magnifica

Location: Brazil
}}

How it made the Top 10: This is believed to be the first new species of plant discovered through photographs posted on Facebook. It is also a record-setter, being the largest sundew ever seen in the New World, growing to 123 cm (48 inches). With nearly 200 species, the sundew genus is one of the most species-rich groups of carnivorous plants. Like other sundews, it secretes a thick mucus on the surface of its leaves that entraps unsuspecting insects that are then digested to compensate for the inadequate nutrition available in the soils in which it grows. Although it is new to science, this sundew is considered to be critically endangered. It is a microendemic, known to exist only at the summit of a single mountain in Brazil, 1,550 meters (5,000 feet) above sea level. Although locally abundant, its habitat is isolated, limited and fragile.

{{Hominin: Family Tree Grows a New Branch

Homo naledi

Location: South Africa
}}

How it made the Top 10: Fossil remains of this previously unknown species of the genus Homo represent at least 15 different individuals, the largest collection of remains of a single species of hominin ever discovered on the African continent. Anatomical features of this new hominin found in South Africa are a mixture of those of Australopithecus with other Homo species, combined with several features not known in any hominin species. Features shared with other Homo species include complex functional locomotion, manipulation and mastication systems. Similar in size and weight to a modern human, and with humanlike hands and feet, the new species has a braincase more similar in size to earlier ancestors living two million to four million years ago, as well as shoulders, pelvis, and ribcage more closely resembling earlier hominins than modern humans. The exact age of the remains, once determined, will have implications for the early history of our genus.

{{Isopod: Working as Architect, Builder

Iuiuniscus iuiuensis

Location: Brazil
}}

How it made the Top 10: This might be the 15 minutes of fame that isopods (crustaceans that live in water or on land; think “pillbug”) have been waiting for. This blind, unpigmented, multilegged animal represents a new subfamily, genus, and species of amphibious isopod discovered in a South American cave. It has a behavior never seen before in its family: It constructs shelters of mud. The cave where the species was discovered has its only entrance at the bottom of a sinkhole and its inner chambers are flooded during the rainy season. Eight other caves in the region were explored, but the new species was found in only one. This isopod, just over 9 mm (a third of an inch) in length, builds spherical, irregularly shaped shelters in which it molts. While shedding its exoskeleton, it is especially vulnerable to predators. Some Palearctic isopods are known to build shelters, but this is a first for the New World. The new species is unique among its Brazilian cave-inhabiting relatives in having tapering plates at the base of its legs that give it a spiny appearance.

{{Anglerfish: Angling for Ugliest

Lasiognathus dinema

Location: Gulf of Mexico}}

How it made the Top 10: If this fish from the Gulf of Mexico, barely 50 mm (about two inches) long, were angling for ugliest among the Top 10 New Species, it might succeed. It was discovered during a Natural Resource Damage Assessment process conducted by the National Oceanic and Atmospheric Administration after the Deepwater Horizon oil spill in 2010. Different species of anglerfish can be distinguished visually only by details of the unusual structure called the esca that is projected over their heads like — ironically — a fishing pole. This organ is located at the tip of a highly modified, elongated dorsal ray. Rays are the spines that add support to the dorsal fin. The esca in some anglerfish is home to symbiotic bacteria that are bioluminescent, producing light that is a rare commodity in the depths of the ocean and is presumed to attract prey. Either way, these are among the most unusual features of any fish in form and function.

{{Seadragon: Ruby Red with Pink Stripes

Phyllopteryx dewysea

Location: Australia}}

How it made the Top 10: Seadragons are related to seahorses and are a unique combination of beautiful and bizarre. This new kind of marine fish, 240 mm (nearly 10 inches) in length, is a striking shade of ruby red with pink vertical bars and light markings on its snout. Only the third known species of seadragon, it is found in slightly deeper and more offshore waters than the related common or leafy seadragons. The discovery was made off the coast of Western Australia. Aside from its spectacular appearance, it is a reminder of what we have yet to discover about marine species diversity. If ruby red dragons nearly a foot long in shallow waters have escaped our attention, what else do we not yet know?

{{Tiny Beetle: Please Look After This Species

Phytotelmatrichis osopaddington

Location: Peru}}

How it made the Top 10: This species owes its charming Latin name to Paddington Bear, a lovable character who became a classic in children’s literature after he was introduced in 1958. As the story goes, he showed up one day in Paddington Station, London, with a sign that said, “Please look after this bear.” Like him, the new beetle hails from Peru. The researchers hope the new species’ name will draw attention to the threatened Andean spectacled bear that inspired the Paddington books. Nearly 25 of these tiny beetles could line up, head to tail, before they reached the one-inch mark on a yardstick. They have a peculiar way of life. A little-studied world of animals, from insects to frogs, make their homes in pools of water that accumulate in hollows of plants, such as tree holes and the leaf bases of bromeliads (tropical and subtropical plants with short stems and stiff, open spiny leaves); these water bodies are called phytotelmata. This species was discovered in such water, gathered in leaf rolls of a non-native, cultivated plant, sparking questions about its food, breeding and native hosts. This is a featherwing beetle, the family that includes the smallest known group of beetles and which is named for the distinctive shape of their wings. Most of them are found on the forest floor where they feed on decomposing materials. So far, the plants documented as hosts to the new species belong to the Zingiberales, an order of flowering plants that include ginger and banana among 2,000 others.

{{New Primate: Small Ape with Big Implications

Pliobates cataloniae

Location: Spain}}

How it made the Top 10: This ape, nicknamed “Laia” by her discoverers, was a small female that lived about 11.6 million years ago in what is now Spain, climbing trees and eating fruit. Fragments of her remains were discovered in a landfill in Catalonia, and she has challenged a lot of assumptions about the origins of, and relations among, living apes, gibbons and humans. It appears she was 4 to 5 kg (roughly 9 to 11 pounds) in weight, suggesting a diminutive height of about 43 cm (17 inches). She lived before the lineage containing humans and great apes had diverged from its sister branch, the gibbons, and she appears to be sister to the three combined. Her discovery suggests greater morphological diversity existed at that time, in the Miocene, than previously thought, and raises the possibility that early humans could have been more closely related to gibbons than the great apes. Her name is a popular Catalan diminutive of the name “Eulàlia,” the original patron saint of the city of Barcelona.

{{Flowering Tree: All the Buzz

Sirdavidia solannona

Location: Gabon
}}

How it made the Top 10: This new tree species was “hidden” just meters from the main road in the Monts de Cristal National Park, in Gabon, which was thought to have already been well explored by science. Its small size, less than 6 meters (20 feet) high with a diameter of 10 cm (about four inches) might have caused it to be overlooked during inventories that focus on larger trees. It is so different from related members of the Annonaceae family of flowering plants, based on both morphology and molecular data, that it was described as a new genus, too. Its closest relative is also a genus with a single species, Mwasumbia, found on the other side of the African continent in Tanzania some 3,000 km (1,865 miles) away. Interestingly, the new species’ flowers resemble those of certain Solanum, the genus of the nightshade family that includes potatoes and tomatoes, that are associated with the “buzz” pollination syndrome. In this syndrome, flowers have reflexed petals exposing the stamens and pistils that bees “sonicate” by creating vibrations of the air with their wings to extract and spread pollen. If buzz pollination is confirmed, it would be the first example in this family or any other early-diverged flowering plant, and an unexpected example of convergent reproductive evolution.

Sparklewing: Damselfly with a Daring Name

{{Umma gumma

Location: Gabon}}

How it made the Top Ten: This new damselfly is just one of a staggering number of newly discovered dragonflies and damselflies from Africa. Sixty new species were reported in a single publication this year, the most for any single paper in more than a century and a surprising leap forward in knowledge for one of the better-known insect orders. Most of the new species are colorful and so distinct they are identifiable from photographs alone, emphasizing that not all unknown species are small, indistinct or cryptic in appearance or habits. Given that the genus name is Umma, it was quick work to give this lovely and delicate damselfly a name that might be familiar to rock-and-roll fans: the band Pink Floyd named its 1969 double album Ummagumma (which has yet another meaning as a British slang term for sex).