Category: Environment

{Sixteen million years ago, the reptile Diplocynodon ratelii lived in wooded ecosystems among the lakes and pools of what we know today as Catalonia (Spain). Fossils found at the Els Casots site in the Vallès-Penedès Basin confirm not only that these are the most recent remains of the genus in the Iberian Peninsula, but also that temperatures at the time were higher than today’s.}

A group of researchers working at the Els Casots site in the 1990s excavated the remains of a species of crocodile that was until then known only to have lived in southern France.

Following several years in storage as they awaited analysis, the fossils have now been confirmed by new research published in the journal Comptes Rendus Palevol to be the first evidence of Diplocynodon ratelii in the Iberian Peninsula, where evidence had previously only been found for other species of this genus.

In addition to this, “these remains represent the latest published evidence of the genus in the Iberian Peninsula, as until now it had only been recorded much less recently, in the Eocene and Oligocene epochs, over 23 million years ago,” Sinc was told by the lead author of the paper, David Alba of the Catalan Institute of Paleontology Miquel Crusafont (ICP).

To reach these conclusions, the study provides the most detailed anatomical descriptions of the species given to date, highlighting the small size of the reptile, which measured no more than a metre long, according to craniums found at the site in Catalonia. Diplocynodon ratelii was a diplocynodon which would have originated prior to the divergence between caimans and alligators.

“The genus Diplocynodon was widely distributed across Europe for over 40 million years (from the Paleocene to the Miocene) and includes many species of small crocodiles similar in appearance to caimans and alligators (the family to which the species belongs, now extinct, is part of the alligatoroidea superfamily, alongside caimans and alligators),” said the researcher.

Fauna in Catalonia during the early Miocene

Today, alligatoroids are more common in the Americas and East Asia, but millions of years ago they were widespread in Eurasia. Diplocynodon ratelii, which is very similar in appearance to today’s caimans, stalked small prey, such as rodents and other extinct fish and reptile species that were present during the early Miocene. It also hunted larger mammals, such as mouse-deer (an artiodactyl).

According to remains found in recent years in Els Casots, these crocodiles would also have shared their habitat with large mammals: rhinoceroses, the equid genus Anchitherium, peccaries, mouse-deer, primitive pigs and bovines, extinct relatives of elephants (including the mastodon and a proto-elephant named deinotherium) and some carnivorous species, such as the so-called bear dogs and felids, hyaenids and extinct mustelids.

The presence of crocodiles in this area of the Iberian Peninsula can be explained by evidence from the analysis of other paleo-environmental remains from the site, from 16 million years ago, which indicate that there was once a lake there.

Given the abundance of fauna remains found in Els Casots, which is listed as an Cultural Asset of National Interest, the research group is very interested in reopening the excavations. Working in collaboration with the municipal government of Subirats, which owns the land, the scientists intend to recover additional fossil remains which may contribute to improving the available information on the fauna, paleo-environment and taphonomy of the site as a whole and on the taxonomy and paleo-biology of specific species.

“Reopening the site could also be linked to other actions to disseminate paleontology and paleontological heritage, although there still needs to be a discussion into how we would go about doing this,” concludes David Alba.

Source:Science Daily

When people think about climate change, they probably think first about its effects on the environment, and possibly on their physical health. But climate change also takes a significant toll on mental health, according to a new report released by the American Psychological Association and ecoAmerica entitled Mental Health and Our Changing Climate: Impacts, Implications, and Guidance.

Climate change-induced severe weather and other natural disasters have the most immediate effects on mental health in the form of the trauma and shock due to personal injuries, loss of a loved one, damage to or loss of personal property or even the loss of livelihood, according to the report. Terror, anger, shock and other intense negative emotions that can dominate people’s initial response may eventually subside, only to be replaced by post-traumatic stress disorder.

As an example of the impacts natural disasters can have, among a sample of people living in areas affected by Hurricane Katrina in 2005, suicide and suicidal ideation more than doubled, one in six people met the diagnostic criteria for PTSD and 49 percent developed an anxiety or mood disorder such as depression, said the report.

The impacts of climate on mental health are not relegated to disasters alone. There are also significant mental health impacts from longer-term climate change. Changes in climate affect agriculture, infrastructure and livability, which in turn affect occupations and quality of life and can force people to migrate. These effects may lead to loss of personal and professional identity, loss of social support structures, loss of a sense of control and autonomy and other mental health impacts such as feelings of helplessness, fear and fatalism. High levels of stress and anxiety are also linked to physical health effects, such as a weakened immune system. Worry about actual or potential impacts of climate change can lead to stress that can build over time and eventually lead to stress-related problems, such as substance abuse, anxiety disorders and depression, according to research reviewed in the report.

Climate change is likewise having mental health impacts at the community level. Both acute and long-term changes have been shown to elevate hostility and interpersonal and intergroup aggression, and contribute to the loss of social identity and cohesion, said the report. Certain disadvantaged communities, such as indigenous communities, children and communities dependent on the natural environment can experience disproportionate mental health impacts.

The key to combating the potential negative psychological effects of climate change, according to the report, is building resilience. It includes a section dedicated to offering guidance to aid professionals in supporting and promoting the mental health of individuals and communities and helping them build psychological resilience. One recommendation is to guide people to support and maintain their social networks.

“Individuals’ personal capacity to withstand trauma is increased when they are connected to their networks off- and online,” said the report. “Researchers have found that higher levels of social support during and in the aftermath of a disaster are associated with lower rates of psychological distress.”

The report also emphasized that adopting environmentally friendly policies and lifestyle choices can have a positive effect on mental health. For example, choosing to bike or walk to work has been associated with decreased stress levels. If walking or biking to work is impractical or unsafe, use of public transportation has been associated with an increase in community cohesion and a reduction in symptoms of depression and stress, according to the report. Also, increased accessibility to parks and other green spaces could benefit mental health as spending more time in nature has been shown to lower stress levels and reduce stress-related illness, regardless of socioeconomic status, age or gender.

The report, which was produced in collaboration with psychologists Susan Clayton, PhD, of the College of Wooster, and Christie Manning, PhD, of Macalester College, is an update to Beyond Storms and Droughts: The Psychological Impacts of Climate Change, a report released by the American Psychological Association and ecoAmerica in 2014. A seminal work on the relationship between climate change and psychology, Beyond Storms and Droughts was cited in the U.S. Global Change Research Program’s scientific assessment, The Impacts of Climate Change on Human Health in the United States. This 2017 update builds on the findings of the first report with new research, expanded emphasis on inequity, deeper guidance for individuals and communities and stories from professionals who are studying and supporting mental health in a changing climate.

Source:Science Daily

{Long before the advent of agriculture, hunter-gatherers began putting down roots in the Middle East, building more permanent homes and altering the ecological balance in ways that allowed the common house mouse to flourish, new research in the Proceedings of the National Academy of Sciences indicates.}

“The research provides the first evidence that, as early as 15,000 years ago, humans were living in one place long enough to impact local animal communities — resulting in the dominant presence of house mice,” said Fiona Marshall, study co-author and a professor of anthropology at Washington University in St. Louis. “It’s clear that the permanent occupation of these settlements had far-reaching consequences for local ecologies, animal domestication and human societies.”

Marshall, a noted expert on animal domestication, considers the research exciting because it shows that settled hunter-gatherers rather than farmers were the first people to transform environmental relations with small mammals. By providing stable access to human shelter and food, hunter-gatherers led house mice down the path to commensalism, an early phase of domestication in which a species learns how to benefit from human interaction.

The findings have broad implications for the processes that led to animal domestication.

“The findings provide clear evidence that the ways humans have shaped the natural world are tied to varying levels of human mobility,” said Marshall, the James W. and Jean L. Davis Professor in Arts & Sciences. “They suggest that the roots of animal domestication go back to human sedentism thousands of years prior to what has long been considered the dawn of agriculture.”

Led by Thomas Cucchi of National Center for Scientific Research in Paris, France, and Lior Weissbrod of the University of Haifa in Israel, the study set out to explain large swings in the ratio of house mice to wild mice populations found during excavations of different prehistoric periods at an ancient Natufian hunter-gatherer site in the Jordan Valley of Israel.

Examining tiny species-related variations in the molar shapes of fossilized mice teeth dating back as far as 200,000 years, the team built a timeline showing how the populations of different mice fluctuated at the Natufian site during periods of varying human mobility.

The analysis revealed that human mobility influenced competitive relationships between two species of mice — the house mouse (Mus musculus domesticus)and a short-tailed field mouse (M. macedonicus) — that continue to live in and around modern settlements in Israel. These relationships are analogous to those of another pair of species called spiny mice which Weissbrod and Marshall discovered among semi-nomadic Maasai herders in southern Kenya.

Findings indicate that house mice began embedding themselves in the Jordan Valley homes of Natufian hunter-gatherers about 15,000 years ago, and that their populations rose and fell based on how often these communities picked up and moved to new locations.

When humans stayed in the same places for long runs of time, house mice out-competed their country cousins to the point of pushing most of them outside the settlement. In periods where drought, food shortages or other conditions forced hunter-gatherers to relocate more often, the populations of house mice and field mice reached a balance similar to that found among modern Maasai herders with similar mobility patterns.

The study confirms that house mice were already a fixture in the domiciles of eastern Mediterranean hunter-gatherer villages more than 3,000 years before the earliest known evidence for sedentary agriculture.

It suggests that the early hunter-gatherer settlements transformed ecological interactions and food webs, allowing house mice that benefited from human settlements to out-compete wild mice and establish themselves as the dominant population.

“The competition between commensal house mice and other wild mice continued to fluctuate as humans became more mobile in arid periods and more sedentary at other times — indicating the sensitivity of local environments to degrees of human mobility and the complexity of human environmental relationships going back in the Pleistocene,” said Weissbrod, currently a research fellow at the Zinman Institute of Archaeology at the University of Haifa.

Weissbrod’s research involves analysis of microvertebrate remains from a wide range of prehistoric and historic sites in Israel and the Caucasus dealing with paleoecology and human-ecosystem interactions.

A 2010 graduate of the doctoral program in archaeological anthropology at Washington University, he began research for this study as part of a dissertation examining fluctuations in populations of mice and other small animals living around Maasai cattle herding settlements in Kenya.

Marshall helped Weissbrod to develop the ethnographic context for underlying research questions about the ecological impact of human mobility. Together they built field-based ecological frameworks for understanding changing animal human interactions through time focusing on mice and donkeys.

Working from his lab in Paris, Cucchi used a new technique called geometric morphometrics to identify the mouse fossils and reliably distinguish telltale differences in the miniscule remains of house mice and wild species. The method relies on high resolution imaging and digital analysis to categorize species-related variations in molar outlines nearly as thin as a single millimeter.

The findings, and the techniques used to document them, are important to archaeological research in a broader sense because they lend further support to the idea that fluctuations in ancient mouse populations can be used as a proxy for tracking ancient shifts in human mobility, lifestyle and food domestication.

“These findings suggest that hunter-gatherers of the Natufian culture, rather than later Neolithic farmers, were the first to adopt a sedentary way of life and unintentionally initiated a new type of ecological interaction — close coexistence with commensal species such as the house mouse,” Weissbrod said. “The human dynamic of shifts between mobile and sedentary existence was unraveled in unprecedented detail in the record of fluctuations in proportions of the two species through time.”

Source:Science Daily

{Brain size in primates is predicted by diet, an analysis by a team of New York University anthropologists indicates. These results call into question “the social brain hypothesis,” which has posited that humans and other primates are big-brained due to factors pertaining to sociality.}

The findings, which appear in the journal Nature Ecology and Evolution, reinforce the notion that both human and non-human primate brain evolution may be driven by differences in feeding rather than in socialization.

“Are humans and other primates big-brained because of social pressures and the need to think about and track our social relationships, as some have argued?” asks James Higham, an assistant professor in NYU’s Department of Anthropology and a co-author of the new analysis. “This has come to be the prevailing view, but our findings do not support it — in fact, our research points to other factors, namely diet.”

“Complex foraging strategies, social structures, and cognitive abilities, are likely to have co-evolved throughout primate evolution,” adds Alex DeCasien, an NYU doctoral candidate and lead author of the study. “However, if the question is: ‘Which factor, diet or sociality, is more important when it comes to determining the brain size of primate species?’ then our new examination suggests that factor is diet.”

The social brain hypothesis sees social complexity as the primary driver of primate cognitive complexity, suggesting that social pressures ultimately led to the evolution of the large human brain. While some studies have shown positive relationships between relative brain size and group size, other studies which examined the effects of different social or mating systems have revealed highly conflicting results, raising questions about the strength of the social brain hypothesis.

In the Nature Ecology and Evolution study, the researchers, who also included Scott Williams, an assistant professor of anthropology at NYU, examined more than 140 primate species — or more than three times as many as previous studies — and incorporated more recent evolutionary trees, or phylogenies. They took into account food consumption across the studied species — folivores (leaves), frugivores (fruit), frugivores/folivores, and omnivores (addition of animal protein) — as well as several measures of sociality, such as group size, social system, and mating system.

Their results showed that brain size is predicted by diet rather than by the various measures of sociality — after controlling for body size and phylogeny. Notably, frugivores and frugivore/folivores exhibit significantly larger brains than folivores and, to a lesser extent, omnivores show significantly larger brains than folivores.

The researchers caution that the results do not reveal an association between brain size and fruit or protein consumption on a within-species level; rather, they note, they are evidence of the cognitive demands required by different species to obtain certain foods.

“Fruit is patchier in space and time in the environment, and the consumption of it often involves extraction from difficult-to-reach-places or protective skins,” observes DeCasien. “Together, these factors may lead to the need for relatively greater cognitive complexity and flexibility in frugivorous species.”

Source:Science Daily

{In a new paper published in National Science Review, a team of scientists from the Institute of Vertebrate Paleontology and Paleoanthropology, the Shandong Tianyu Museum of Nature, and the Nanjing Institute of Geology and Paleontology (all in China) described the most exceptionally preserved fossil bird discovered to date.}

The new specimen from the rich Early Cretaceous Jehol Biota (approximately 131 to 120 million years old) is referred to as Eoconfuciusornis, the oldest and most primitive member of the Confuciusornithiformes, a group of early birds characterized by the first occurrence of an avian beak. Its younger relative Confuciusornis is known from thousands of specimens but this is only the second specimen of Eoconfuciusornis found. This species comes only from the 130.7 Ma Huajiying Formation deposits in Hebei, which preserves the second oldest known fossil birds. Birds from this layer are very rare.

This new specimen of Eoconfuciusornis, housed in the Shandong Tianyu Museum of Nature, in Eastern China, is a female. The ovary reveals developing yolks that vary in size, similar to living birds. This suggests that confuciusornithiforms evolved a period of rapid yolk deposition prior to egg-laying (crocodilians, which are archosaurs like birds, deposit yolks slowly in all eggs for months with no period of rapid yolk formation), which is indicative of complex energetic profiles similar to those observed in birds.

This means Eoconfuciusornis and its kin, like living birds, was able to cope with extremely high metabolic demands during early growth and reproduction (whereas energetic demands in crocodiles are even, lacking complexity). In contrast, other Cretaceous birds including the more advanced group the Enantiornithes appear to have lower metabolic rates and have required less energy similar to crocodilians and non-avian dinosaurs (their developing yolks show little size disparity indicating no strong peak in energy associated with reproduction, and much simpler energetic profiles, limited by simpler physiologies).

Traces of skin indicate that the wing was supplemented by flaps of skin called patagia. Living birds have numerous wing patagia that help the bird to fly. This fossil helps show how bird wings evolved. The propatagium (the flap of skin that connects the shoulder and wrist) and postpatagium (the flap of skin that extends off the back of the hand and ulna) evolved before the alular patagium (the flap of skin connecting the first digit to the rest of the hand), which is absent in Eoconfuciusornis. Even more unique is the preservation of the internal structure of the propatagium which reveal a collagenous network identical to that in living birds. This internal network gives the skin flap its shape, allowing it to generate aerodynamic lift and aid the bird in flight.

The nearly complete plumage preserves remnants of the original plumage pattern, revealing the presence of spots on the wings and the earliest documentation of sexual differences in plumage within birds. This new specimen suggests that female Eoconfuciusornis were smaller than males and lacked tail feathers, similar to many sexually dimorphic living birds and the younger Confuciusornis in which the plumage of the males and females are different from each other. Samples of the feathers viewed under a microscope reveal differences in color characteristics, allowing scientists to reconstruct the plumage. Female Eoconfuciusornis had black spotted wings and gray body with a red throat patch.

Researchers have not found fossils from any other bird from the Jehol period that reveal so many types of soft tissue (feathers, skin, collagen, ovarian follicles). These remains allow researchers to create the most accurate reconstruction of a primitive early bird (or dinosaur) to date. This information provides better understanding of flight function in the primitive confuciusornithiforms and of the evolution of advanced flight features within birds.

“This new fossil is incredible,” said co-author Dr. Jingmai O’Connor. “With the amount of information we can glean from this specimen we can really bring this ancient species to life. We can understand how it grew, flew, reproduced, and what it looked like. Fossils like this one from the Jehol Biota continue to revolutionize our understanding of early birds.”

Source:Science Daily

{A 20-year demographic study of a large chimpanzee community in Uganda’s Kibale National Park has revealed that, under the right ecological conditions, our close primate relatives can lead surprisingly long lives in the wild.}

The study, published March 19 in the Journal of Human Evolution, establishes an average life expectancy of about 33 years in its sample of 306 chimpanzees, nearly twice as high as that of other chimpanzee communities and within the 27- to 37-year range of life expectancy at birth of human hunter-gatherers. These findings are important for understanding the evolution of chimpanzee and hominin life histories, the researchers argue.

“Our findings show how ecological factors, including variation in food supplies and predation levels, drive variation in life expectancy among wild chimpanzee populations,” said Brian Wood, assistant professor of anthropology at Yale University, the study’s lead author. “They also inform the study of the evolution of human life history, helping us to imagine the conditions that could have changed mortality rates among our early hominin populations.”

The Ngogo chimpanzees reside in the center of Kibale National Park, in southwestern Uganda. The directors of the Ngogo Chimpanzee Project — David Watts (Yale), John Mitani (University of Michigan), and Kevin Langergraber (Arizona State University) — have monitored births, deaths, immigrations, and emigrations in the unusually large Ngogo chimpanzee community since 1995, producing the largest demographic dataset available for any community of wild chimpanzees. This study reveals that Ngogo chimpanzees have the highest life expectancy on record for any group of wild chimpanzees.

Favorable ecological conditions largely account for the Ngogo community’s high life expectancy, according to the study. The forest in Ngogo provides a relatively consistent and abundant supply of high-energy and nutritious foods, including easily digestible figs. The research team argues that this rich food supply helps buffer the Ngogo chimpanzees against periods of hunger, and helps fuel their ability to stave off diseases that would otherwise lead to higher mortality. The Ngogo chimpanzees also benefit from a low risk of predation, because leopards are not found within Kibale National Park, and from the fact that during the study, the chimpanzees did not experience major disease epidemics, either introduced by humans or due to other causes, like those that have affected wild chimpanzees at several other long-term research sites.

In the same national park, not far from Ngogo, other researchers have studied the life expectancy of chimpanzees in the Kanyawara community. Like Ngogo, this community lacks natural predators, but its life expectancy at birth is nearly 13 years shorter than that of Ngogo. The Ngogo chimpanzees’ higher survivorship appears to be an adaptive response to a more abundant and less varied food supply than that of Kanyawara, the researchers argue.

“It has long been proposed that there are extreme differences in the life expectancies of human hunter-gatherers and chimpanzees,” said David Watts, professor of anthropology at Yale and a coauthor of the study. “Our study finds that while maximum lifespan differs a great deal, the differences in average lifespan are not as dramatic as typically thought, especially when chimpanzees are not subjected to major negative impacts caused by humans. In fact, the Ngogo community’s pattern of survivorship more closely resembles that of human hunter-gatherers than those documented for other chimpanzee communities.”

Source:Science Daily

{New NASA research reveals that the giant Martian shield volcano Arsia Mons produced one new lava flow at its summit every 1 to 3 million years during the final peak of activity. The last volcanic activity there ceased about 50 million years ago — around the time of Earth’s Cretaceous-Paleogene extinction, when large numbers of our planet’s plant and animal species (including dinosaurs) went extinct.}

Located just south of Mars’ equator, Arsia Mons is the southernmost member of a trio of broad, gently sloping shield volcanoes collectively known as Tharsis Montes. Arsia Mons was built up over billions of years, though the details of its lifecycle are still being worked out. The most recent volcanic activity is thought to have taken place in the caldera — the bowl-shaped depression at the top — where 29 volcanic vents have been identified. Until now, it’s been difficult to make a precise estimate of when this volcanic field was active.

“We estimate that the peak activity for the volcanic field at the summit of Arsia Mons probably occurred approximately 150 million years ago — the late Jurassic period on Earth — and then died out around the same time as Earth’s dinosaurs,” said Jacob Richardson, a postdoctoral researcher at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “It’s possible, though, that the last volcanic vent or two might have been active in the past 50 million years, which is very recent in geological terms.”

Richardson is presenting the findings on March 20, 2017, at the Lunar and Planetary Science Conference in The Woodlands, Texas. The study also is published in Earth and Planetary Science Letters.

Measuring about 68 miles (110 kilometers) across, the caldera is deep enough to hold the entire volume of water in Lake Huron, and then some. Examining the volcanic features within the caldera required high-resolution imaging, which the researchers obtained from the Context Camera on NASA’s Mars Reconnaissance Orbiter.

The team mapped the boundaries of the lava flows from each of the 29 volcanic vents and determined the stratigraphy, or layering, of the flows. The researchers also performed a technique called crater counting — tallying up the number of craters at least 330 feet (100 meters) in diameter — to estimate the ages of the flows.

Using a new computer model developed by Richardson and his colleagues at the University of South Florida, the two types of information were combined to determine the volcanic equivalent of a batting lineup for Arsia Mons’ 29 vents. The oldest flows date back about 200 million years. The youngest flows probably occurred 10 to 90 million years ago — most likely around 50 million years ago.

The modeling also yielded estimates of the volume flux for each lava flow. At their peak about 150 million years ago, the vents in the Arsia Mons’ caldera probably collectively produced about 1 to 8 cubic kilometers of magma every million years, slowly adding to the volcano’s size.

“Think of it like a slow, leaky faucet of magma,” said Richardson. “Arsia Mons was creating about one volcanic vent every 1 to 3 million years at the peak, compared to one every 10,000 years or so in similar regions on Earth.”

A better understanding of when volcanic activity on Mars took place is important because it helps researchers understand the Red Planet’s history and interior structure.

“A major goal of the Mars volcanology community is to understand the anatomy and lifecycle of the planet’s volcanoes. Mars’ volcanoes show evidence for activity over a larger time span than those on Earth, but their histories of magma production might be quite different,” said Jacob Bleacher, a planetary geologist at Goddard and a co-author on the study. “This study gives us another clue about how activity at Arsia Mons tailed off and the huge volcano became quiet.”

Source:Science Daily

{With the first day of spring around the corner, temperatures are beginning to rise, ice is melting, and the world around us is starting to blossom. Scientists sometimes refer to this transition from winter to the growing season as the “vernal window,” and a new study led by the University of New Hampshire shows this window may be opening earlier and possibly for longer.
}

“Historically, the transition into spring is comparatively shorter than other seasons,” said Alexandra Contosta, a research assistant professor at the University of New Hampshire’s Earth Systems Research Center. “You have snow melting and lots of water moving through aquatic systems, nutrients flushing through that water, soils warming up, and buds breaking on trees. Something striking happens after a very cold winter or when there’s been a lot of snow. Things seem to wake up all together, which is why spring seems to happen so quickly and can feel so dramatic.”

However, research shows that the Northern Hemisphere snow cover extent has declined significantly in the past 30 years. To see if this may be influencing the so-called vernal window, or the transition from winter into spring, Contosta led a team of scientists that collected data from a network of New Hampshire EPSCoR soil and water sensors installed across the state. They monitored snow levels and the forest canopy for three years. Their information was supplemented with climate and satellite data along with precipitation and stream data collected by more than 100 volunteers across the state. They not only looked at dates when certain events occurred that marked the seasonal transition, such as the melting of snow and the emergence of leaves in trees, but also the time period between these events. Their findings, published early online in the journal Global Change Biology, showed that warmer winters with less snow resulted in a longer lag time between spring events and a more protracted vernal window.

This type of changing timetable for spring may have potential ecological, social, and economic consequences that Contosta and her team are currently investigating. Agriculture, fisheries, and even outdoor recreation activities can be highly dependent on the timing of springtime climate conditions. A longer spring could mean a longer mud season requiring more road repairs and truck weight restrictions, a possible shift in the duration of the sugar maple season, or earlier lake thaw which might have implications with migratory birds. The ice melts earlier, but the birds may not have returned yet, causing a delay, or lengthening, in springtime ecological events.

The researchers plan to test their conclusions with data from a larger geographic area and over longer periods.

Source:Science Daily