With more than 350 new fossils, the 15-year study pieces together a nearly complete picture of the skeletal anatomy of the Cambaytherium — an extinct cousin of perissodactyls that lived on the Indian subcontinent almost 55 million years ago.

Among the findings includes a sheep-sized animal with moderate running ability and features that were intermediate between specialized perissodactyls and their more generalized mammal forerunners. Comparing its bones with many other living and extinct mammals, revealed that Cambaytherium represents an evolutionary stage more primitive than any known perissodactyl, supporting origin for the group in or near India — before they dispersed to other continents when the land connection with Asia formed.

This new landmark article was selected for publication as a part of the Society of Vertebrate Paleontology Memoir Series, a special yearly publication that provides a more in-depth analysis of the most significant vertebrate fossils.

Cambaytherium, first described in 2005, is the most primitive member of an extinct group that branched off just before the evolution of perissodactyls, providing scientists with unique clues to the ancient origins and evolution of the group.

“The modern orders Artiodactyla (even-toed ungulates), Perissodactyla, and Primates appeared abruptly at the beginning of the Eocene around 56 million years ago across the Northern Hemisphere, but their geographic source has remained a mystery,” explained Ken Rose, emeritus professor at Johns Hopkins University and lead author of the study.

Prof. Rose became intrigued by a new hypothesis suggesting that perissodactyls may have evolved in isolation in India. Then India was an island continent drifting northwards, but it later collided with the continent of Asia to form a continuous landmass.

“In 1990, Krause & Maas proposed that these orders might have evolved in India, during its northward drift from Madagascar, dispersing across the northern continents when India collided with Asia.”

Armed with this new hypothesis, Rose and colleagues obtained funding from The National Geographic Society to explore India for rare fossil-bearing rocks of the correct age that might provide critical evidence for the origin of perissodactyls and other groups of mammals.

The first trip to Rajasthan in 2001 had little success, “Although we found only a few fish bones on that trip, the following year our Indian colleague, Rajendra Rana, continued exploring lignite mines to the south and came upon Vastan Mine in Gujarat.”

This new mine proved much more promising. Rose added: “In 2004 our team was able to return to the mine, where our Belgian collaborator Thierry Smith found the first mammal fossils, including Cambaytherium.”

Encouraged, the team returned to the mines and collected fossilized bones of Cambaytherium and many other vertebrates, despite challenging conditions.

“The heat, the constant noise and coal dust in the lignite mines were tough — basically trying to work hundreds of feet down near the bottom of open-pit lignite mines that are being actively mined 24/7,” he said.

Through the cumulation of many years of challenging fieldwork, the team can finally shed light on a mammal mystery. Despite the abundance of perissodactyls in the Northern Hemisphere, Cambaytherium suggests that the group likely evolved in isolation in or near India during the Paleocene (66-56 million years ago), before dispersing to other continents when the land connection with Asia formed.

Many species of birds have always migrated south in the fall to spend the winter there, including the small blackcap, which often weighs only a few grams and yet covers thousands of kilometers. However, changes in our landscapes and climate change are not leaving migratory birds unaffected. They change their behavior, the destinations of their journey, the time of their departure or even the decision whether to fly away at all. So far, these habits have been studied either experimentally with birds in captivity or by irregular recaptures of ringed birds.

A group of international researchers led by Miriam Liedvogel from the Max Planck Institute for Evolutionary Biology in Plön has now for the first time conducted a large-scale study with geolocators. These are ultra-light, tiny devices that are attached to the backs of free-flying birds and record the light intensity with exact time data. After the birds have been caught again, the respective flight route can be calculated exactly. Altogether the scientists could document and analyze the migrations of 100 individual birds.

Different migration destinations depending on the breeding area

It was already known beforehand that there is a migration divide in Europe: east of this imaginary line, the blackcaps migrate southeast in the fall, and west of this line, they move southwest. Through targeted breeding experiments, it was already successfully shown in the 1990s that the direction of migration is inherited by the parents. These experiments also showed that offspring crossed in captivity between western- and easterly blackcaps show an intermediate orientation, i.e. they migrate exactly in the direction of the south. The assumption was that this would be avoided in nature, since the southern route would lead the birds over the Alps, the Mediterranean and possibly over the Sahara desert.

The scientists were now able to show that this intermediate orientation direction does indeed occur in nature and that the birds that choose this migratory direction also successfully return to their breeding areas despite the ecological barriers they have to overcome in this way. The area in which the orientation preference changes is surprisingly narrow and covers only 27 kilometers.

Some birds move north

Another exciting finding from the data obtained concerns a group of birds which, at the end of the year, do exactly the opposite of what one would expect: they do not migrate to the warm south but northwards and spend the winter in Great Britain. Since the 1960s, there has been a steady increase in the number of blackcaps that choose this strategy, probably due to milder winters and the winter feeding in English gardens. The new investigations show for the first time that these birds come from brood-areas scattered over whole Europe. Why do they not let themselves be dissuaded from this strategy by uncomfortable winters?

On the basis of the evaluated data it was to be recognized that these birds returned in the spring approximately ten days earlier to their breeding places than those which spent the winter in the south. The hibernators from Great Britain possibly had an advantage in the search for breeding places. For the evolutionary scientists, these findings are only a beginning. Bird migration behavior is largely genetic, and this study now lays the groundwork for finding the genes that control where birds migrate and when they fly.

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The study published this week in Science Advances was led by the Japan Agency for Marine-Earth Science and Technology, with contributing authors in the United States, United Arab Emirates, Finland and Canada.

According to the research, major Arctic rivers contribute significantly more heat to the Arctic Ocean than they did in 1980. River heat is responsible for up to 10% of the total sea ice loss that occurred from 1980 to 2015 over the shelf region of the Arctic Ocean. That melt is equivalent to about 120,000 square miles of 1-meter thick ice.

“If Alaska were covered by 1-meter thick ice, 20% of Alaska would be gone,” explained Igor Polyakov, co-author and oceanographer at the University of Alaska Fairbanks’ International Arctic Research Center and Finnish Meteorological Institute.

Rivers have the greatest impact during spring breakup. The warming water dumps into the ice-covered Arctic Ocean and spreads below the ice, decaying it. Once the sea ice melts, the warm water begins heating the atmosphere.

The research found that much more river heat energy enters the atmosphere than melts ice or heats the ocean. Since air is mobile, this means river heat can affect areas of the Arctic far from river deltas.

The impacts were most pronounced in the Siberian Arctic, where several large rivers flow onto the relatively shallow shelf region extending nearly 1,000 miles offshore. Canada’s Mackenzie River is the only river large enough to contribute substantially to sea ice melt near Alaska, but the state’s smaller rivers are also a source of heat.

Polyakov expects that rising global air temperatures will continue to warm Arctic rivers in the future. As rivers heat up, more heat will flow into the Arctic Ocean, melting more sea ice and accelerating Arctic warming.

Rivers are just one of many heat sources now warming the Arctic Ocean. The entire Arctic system is in an extremely anomalous state as global air temperatures rise and warm Atlantic and Pacific water enters the region, decaying sea ice even in the middle of winter. All these components work together, causing positive feedback loops that speed up warming in the Arctic.

“It’s very alarming because all these changes are accelerating,” said Polyakov. “The rapid changes are just incredible in the last decade or so.”

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Despite 300 years of research, and a recent renaissance in the study of their biological make-up, the mysterious, marauding teleosauroids have remained enduringly elusive.

Scientific understanding of this distant cousin of present day long snouted gharials has been hampered by a poor grasp of their evolutionary journey — until now.

Researchers from the University of Edinburgh have identified one previously unknown species of teleosauroid and seven of its close relatives — part of a group that dominated Jurassic coastlines 190 to 120 million years ago.

Their analysis offers tantalising glimpses of how teleosauroids adapted to the momentous changes that occurred during the Jurassic period, as the earth’s seas experienced many changes in temperature.

“Our study just scratches the surface of teleosauroid evolution,” says study lead Dr Michela M. Johnson, of the University’s School of GeoSciences. “But the findings are remarkable, raising interesting questions about their behaviour and adaptability.

“These creatures represented some of the most successful prehistoric crocodylomorphs during the Jurassic period and there is so much more to learn about them.”

The study reveals that not all teleosauroids were engaged in cut and thrust lifestyles, snapping at other reptiles and fish from the seas and swamps near the coast.

Instead, they were a complex, diverse group that were able to exploit different habitats and seek out a variety of food sources. Their physical make-up is also more diverse than was previously understood, the scientists say.

Previous research had provided insights into the origins and evolution of this fossilised croc’s whale-like relatives metriorhynchids, but less was known about teleosauroids.

To address this, the expert team of palaeontologists examined more than 500 fossils from more than 25 institutions around the world.

Cutting edge computer software enabled the team to glean swathes of revealing data regarding their anatomical similarities and differences, by examining the entire skeleton, teeth and bony armor, which indicated whether species were closely related or not.

This information enabled the team to create an up-to-date family tree of the teleosauroids group from which emerged two new large groups, whose anatomy, abundance, habitat, geography and feeding styles differ from one another significantly.

The first group, teleosaurids, were more flexible in terms of their habitat and feeding. The second group known as machimosaurids — which included the fearsome turtle crushers, Lemmysuchus and Machimosaurus — were more abundant and widespread.

Names given by the team to seven newly described fossils, found in both teleosaurids and machimosaurids, reflect a curious range of anatomical features — among them Proexochokefalos, meaning ‘large head with big tuberosities’ and Plagiophthalmosuchus, the ‘side-eyed crocodile’.

There are even hints of their diverse behavioural characteristics and unique locations — Charitomenosuchus, meaning ‘graceful crocodile’ and Andrianavoay, the ‘noble crocodile’ from Madagascar.

Researchers have named the newly discovered species, Indosinosuchus kalasinensis, after the Kalasin Province in Thailand, where the fossil — now housed in Maha Sarakham University — was found.

The recognition of I. kalasinensis shows that at least two species were living in similar freshwater habitats during the Late Jurassic — an impressive feat as teleosauroids, with the exception of Machimosaurus, were becoming rare during this time.

Dr Steve Brusatte, Reader in Vertebrate Palaentology, at the School of Geosciences, University of Edinburgh, said: “The same way family trees of our own ancestors and cousins tell us about our history, this huge new family tree of teleosauroids clarifies their evolution. They were some of the most diverse and important animals in the Jurassic oceans, and would have been familiar sights along the coastlines for tens of millions of years.”

The study, published in the scientific journal PeerJ, was funded by the Natural Sciences and Engineering Council of Canada, SYNTHESYS Project and Leverhulme Trust Research. The Palaeontological Association and Paleontological Society provided travel grants.

It’s an important long-term question for policymakers seeking to increase renewable electricity production, cost-effectiveness and efficiency with limited budgets, says C.-Y. Cynthia Lin Lawell, associate professor in the Charles H. Dyson School of Applied Economics and Management at Cornell University.

In a new study focused on Denmark, a global leader in wind energy — a relatively mature and low-cost renewable technology — Lin Lawell found that government policies have been the primary driver of that industry’s growth and development.

“Technological progress alone wouldn’t have led to that widespread development of wind energy in Denmark,” said Lin Lawell, the Robert Dyson Sesquicentennial Chair in Environmental, Energy and Resource Economics. “Well-designed policy may be an important contributor for nascent industries like renewables, which need to develop technology and which have broader societal benefits in terms of the environment.”

Lin Lawell is the co-author with Jonathan Cook, an associate in her DEEP-GREEN-RADAR research group, of “Wind Turbine Shutdowns and Upgrades in Denmark: Timing Decisions and the Impact of Government Policy,” published in a recent issue of The Energy Journal.

Wind turbines in many countries are approaching the end of their useful lives of roughly 20 years, Cook and Lin Lawell note, making decisions about whether to scrap or upgrade them increasingly relevant.

Denmark is ahead of that curve, having promoted wind energy since the oil crisis in the late 1970s. The country produces over 40% of its electricity from wind power and dominates other countries, the authors said, in wind deployment per capita and per gross domestic product. The Danish wind industry is highly decentralized, with 88% of the nearly 3,000 producers included in the 32-year study period from 1980-2011 operating no more than two turbines.

The researchers built a dynamic structural econometric model that incorporated the capacity, age and location of every turbine operated by small producers during that period. The model’s “bottom-up” approach enabled analysis of individual owners’ decisions to shut down, upgrade or add turbines over time, and simulated outcomes if government policies had been scaled back or were not implemented.

“Understanding the factors that influence individual decisions to invest in wind energy and how different policies can affect the timing of these decisions is important for policies both in countries that already have mature wind industries,” the researchers wrote, “as well as in regions of the world that are earlier in the process of increasing renewable electricity generation (e.g. most of the U.S.).”

Denmark since the late 1970s has offered a feed-in tariff that guaranteed producers a fixed price per amount of wind energy generated, whether turbines were new or old. Since 1999, replacement certificates have incentivized upgrades.

Both policies significantly impacted small producers’ shutdown and upgrade decisions and accelerated the development of Denmark’s wind industry, the scholars concluded. Without them, the model showed most small-scale wind producers would have left the industry by 2011, concentrating production in larger wind farms.

However, the analysis determined that replacement certificates were far more cost-effective than the feed-in tariff in encouraging small producers to add or upgrade turbines, helping Denmark reduce its carbon emissions.

The study estimated the Danish government spent $3.5 billion on the feed-in tariff program over the study period, and as much as $114 million on the replacement certificates. Together, the two programs reduced carbon emissions by 57.4 million metric tons of carbon dioxide.

“One was just really expensive at doing it,” Lin Lawell said. “Both the cost per metric ton of carbon dioxide avoided, and the cost per percentage point increase in payoff to the turbine owner, are much lower for the replacement certificate program.”

For every million metric tons of carbon dioxide avoided, the researchers estimated the feed-in tariff cost Danish taxpayers $61.8 million, compared to $2.2 million or less for the replacement certificates.

Cook and Lin Lawell said their analysis offers lessons about the role of government policy in incentivizing the development of renewables and about which policies generate the most bang for the buck.

“Our application to the Danish wind industry,” they wrote, “has important implications for the design of renewable energy policies worldwide.”