South American Miocene mammals, new research


This 2013 video is called John Flynn on Extreme [prehistoric] Mammals South America.

From the University of Arizona in the USA:

Climate, grasses and teeth: The evolution of South America mammals

April 29, 2019

Grass-eating mammals, including armadillos as big as Volkswagens, became more diverse in South America about 6 million years ago because shifts in atmospheric circulation drove changes in climate and vegetation, according to a University of Arizona-led research team.

Geoscientists already knew the Earth was cooling 7 to 5.5 million years ago, a period of time known as the Late Miocene.

However, the changes in ocean climate during that time have been better understood than changes in the continental climate, said lead author Barbara Carrapa, professor and head of the UA department of geosciences.

The new research shows that about 7 to 6 million years ago, the global tropical atmospheric circulation known as the Hadley circulation intensified. As a result, the climate of South America became drier, subtropical grasslands expanded and the numbers of mammal species that were good at eating grasses increased.

Carrapa and her colleagues used a computer model to figure out that the Hadley circulation had strengthened in the late Miocene, altering the climate. They then compared the model’s predictions of the past climate with the natural archives of rainfall and vegetation stored in ancient soils. The model’s predictions agreed with the natural archives.

“We found a strong correlation between this big change in late Miocene climate and circulation that affected the ecology — the plants and animals,” she said. “It has implications for ecosystem evolution.”

Carrapa said the new research — an unusual blend of mammalian paleontology, the geochemistry of ancient soils and global climate computer models — provides a new understanding of the late Miocene, a time when near-modern ecosystems became established.

The paper, “Ecological and hydroclimate responses to strengthening of the Hadley circulation in South America during the Late Miocene Cooling,” by Carrapa, Mark Clementz of the University of Wyoming in Laramie and Ran Feng of the University of Connecticut in Storrs is scheduled for publication the week of April 29 in the Proceedings of the National Academy of Sciences. The National Science Foundation funded the research.

Geoscientists use the geochemistry of ancient soils, specifically forms of the elements oxygen and carbon, to infer past precipitation and vegetation. Researchers had thought the precipitation at the time the soil formed was mostly a function of the site’s topography and elevation.

Carrapa wanted to test that idea by looking at the geochemistry of ancient soils on a continental scale. She teamed up with her long-time colleague Clementz, a paleontologist.

The researchers compiled the published data of the oxygen-18/oxygen-16 ratio and carbon-13/carbon-12 ratio from ancient soils covering a wide swath of South America — from 15 degrees South latitude to 35 degrees South latitude, or about the change from La Paz, Bolivia to Buenos Aires, Argentina. Changes in the oxygen ratio provide information on past precipitation, while changes in carbon ratio indicate what plants were growing at the time.

Clementz scoured the published literature and did what Carrapa called .” .. an amazing job of pulling all the data together so we could look at it in a comprehensive way.”

The results were surprising, Carrapa said. The changes in soil geochemistry during the late Miocene changed in latitudinal bands from north to south, indicating an underlying cause spanning much of South America, not just local changes in elevation or topography.

The two researchers thought the systematic shifts in soil geochemistry were related to changes in climate, so they asked Feng to help them by applying the global climate model she used for research.

Feng loaded known information about the Miocene-to-late-Miocene climate, including atmospheric carbon dioxide concentrations and the ocean temperatures, into the computer model and then asked it to simulate three different versions of late Miocene climate — not much cooler, cooler, and much cooler than before. In each case, the simulation indicated what soil geochemistry would have occurred under that climate regime.

The team found the geochemistry of South American ancient soils predicted by the model matches the geochemistry of the actual soil samples.

Feng figured out that the Earth’s Hadley circulation intensified from 7 to 6 million years ago.

“The records compiled by Barbara and Mark could be explained by a significant change in the strength of the Hadley circulation,” she said.

Feng’s work with the global climate model shows how the past climate could have created the patterns the team was seeing in the soil geochemistry, Clementz said.

The carbon ratio from the ancient soils reflects the vegetation of the time and indicates that in the late Miocene, grasslands were expanding as the climate was changing.

“During the late Miocene, things are starting to dry out, particularly in the 25-30 degree South zone,” he said. “There’s also an increase in the numbers of animals with high-crowned or ever-growing teeth.”

Grasses contain silica, an abrasive substance, which is why grass-eaters have either high-crowned teeth or teeth that continue to grow. The mammals that became more prevalent in the late Miocene included giant armadillos and rhinoceros-like animals and also smaller mammals, he said.

Carrapa said, “Looking at geological pasts is like looking at different planets. The state of the Earth we see today is very different from the Earth of 10 million years ago, 6 million years ago — it’s a different planet. You have the possibility of looking at a different planet through the lens of time, and with the geological record we can do that.”

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Protecting American migratory birds


This March 2017 video from the USA says about itself:

Bird Migration in North America

An overview on how and why birds migrate, including species such as the Yellow Warbler and the Woodthrush, as well as challenges migratory birds face today. This educational video was completed for ‘Birds Ecosystems and People’ at Allegheny College.

From Cornell University in the USA:

Scientists use eBird data to propose optimal bird conservation plan

The goal is to conserve habitat and protect migratory birds

April 15, 2019

A new paper published today in the journal Nature Communications shows a blueprint for conserving enough habitat to protect the populations of almost one-third of the warblers, orioles, tanagers, and other birds that migrate among the Americas throughout the year.

For the research, an international team of scientists used the Cornell Lab of Ornithology’s global citizen science database, eBird, to calculate how to sufficiently conserve habitat across the Western Hemisphere for all the habitats these birds use throughout their annual cycle of breeding, migration, and overwintering. The study provides planners with guidance on the locations and amounts of land that must be conserved for 30 percent of the global populations for each of 117 Neotropical migratory bird species.

More than a third of Neotropical migratory birds are suffering population declines, yet a 2015 global assessment found that only 9 percent of migratory bird species have adequate habitat protection across their yearly ranges to protect their populations. Conservation of migratory birds has historically been difficult, partly because they require habitat across continents and conservation efforts have been challenged by limited knowledge of their abundance and distribution over their vast ranges and throughout the year.

“We are excited to be the first to use a data-driven approach that identifies the most critical places for bird conservation across breeding, overwintering, and migratory stopover areas throughout the Western Hemisphere. In doing so, we provide guidance on where, when, and what type of habitat should be conserved to sustain populations,” said Richard Schuster, Liber Ero Postdoctoral Fellow at Carleton University, and lead author on the Nature Communications paper. “This is a vital step if conservationists are to make the best use of limited resources and address the most critical problems at a hemispheric scale.”

The team’s analysis found that conservation strategies were most efficient when they incorporated working lands, such as agriculture or forestry, rather than exclusively focusing on areas with limited human impacts (i.e., intact or undisturbed landscapes). The importance of shared-use or working landscapes to migratory birds underscores how strategic conservation can accommodate both human livelihoods and biodiversity. The research also found that efficiency was greatest — requiring 56 percent less land area — when planning across the entire year in full, rather than separately by week.

“Efforts to conserve migratory species have traditionally focused on single species and emphasized breeding grounds. Our results show that planning for multiple species across the entire year represents a far more efficient approach to land use planning,” said Scott Wilson, Environment and Climate Change Canada research scientist and co-author on the paper.

“This study illustrates how globally crowd-sourced data can facilitate strategic planning to achieve the best return on conservation investments. No other data source could have achieved anything close to this level of detail and efficiency in spatial planning over such a vast area,” said Cornell Lab senior conservation science director and co-author Amanda Rodewald.

“Prioritizing sites in which to invest our conservation dollars will dramatically improve our returns on the roughly $1 billion spent annually on the conservation of birds by government and nonprofit organizations, often in the absence of spatially explicit information on year-round abundance or geographical representation,” said Peter Arcese, co-author and FRBC Chair in Applied Conservation Biology at University of British Columbia.

Kinkajou on video


This 14 April 2019 video says about itself:

On this episode of Breaking Trail: Legacy Series, we take a look back at the time that Coyote encountered and fed one ferociously adorable KINKAJOU! How adorable do you think he is on a scale of 1-10?! We’re thinking a 10!

Kinkajous live in Central and South America.

American migratory birds and climate change


This 2016 video from North America says about itself:

Where do Golden-winged and Cerulean Warblers go when they migrate? A collaboration between multiple universities is seeking to answer this question. Using light level geolocators, researchers are mapping the migration of these tiny songbirds. The goal is to share their findings to protect and manage habitat for these birds on their migratory route, wintering grounds, and breeding sites for full lifecycle conservation.

From Cornell University in the USA:

How will the winds of climate change affect migratory birds?

New study finds both positive and negative impacts possible

December 10, 2018

Under future climate scenarios, changing winds may make it harder for North American birds to migrate southward in the autumn, but make it easier for them to come back north in the spring. Researchers from the Cornell Lab of Ornithology came to this conclusion using data from 143 weather radar stations to estimate the altitude, density, and direction birds took during spring and autumn migrations over several years. They also extracted wind data from 28 different climate change projections in the most recent report from the Intergovernmental Panel on Climate Change (IPCC). Their findings were published today in the journal Global Change Biology.

“We combined these data to estimate how wind assistance is expected to change during this century under global climate change,” explains lead author Frank La Sorte, a Cornell Lab of Ornithology scientist. “This matters for migratory birds because they use more energy flying into headwinds. But they get a nice boost from tailwinds so they can conserve energy during flight.”

La Sorte and co-authors project that winds from the south are expected to become stronger by the end of the century during both spring and fall migration periods. Winds from the west may be stronger during spring migration and slightly weaker during the fall. Westerly winds are much more variable overall and harder to predict because they are tied to erratic fluctuations in the high altitude jet stream. Wind changes will be most pronounced in the central and eastern portions of the continent.

With an assist from stronger tailwinds during spring migration, birds would likely arrive in better condition on their northern breeding grounds with better odds of survival. Their fall migration flights into stronger headwinds would drain more energy. If headwinds are too strong, birds may choose not to fly at all on a particular night, throwing off the timing of their migrations.

“The thing to remember about these projected wind changes is that they will not occur in isolation,” La Sorte says. “There will be other global change factors for birds to contend with, including changes in temperatures, rainfall, and land cover.”

Some birds may be able to adapt because the expected wind changes are likely to happen gradually. Studies also show that migratory birds already adjust their migration strategy under current conditions, altering their headings to compensate for winds that push them from their intended flight path.

“The bottom line is that some climate change effects could be negative for migratory birds, and some might even be positive, at least during a specific phase of their migration,” says La Sorte. “There’s an awful lot of uncertainty because both climate and migration are complex systems that can intersect in many different ways.”

The breeding seasons of wild house finches are shifting due to climate change, a Washington State University researcher has found: here.

South American marsupials climb higher than thought


This February 2018 video from Chile is called Monito del monte (Dromiciops gliroides).

From the Ecological Society of America:

South American marsupials discovered to reach new heights

For the first time, scientists catch on camera a tiny marsupial climbing higher than previously thought in the forest canopy

October 18, 2018

In the Andean forests along the border of Chile and Argentina, there have long been speculations that the mouse-sized marsupial monito del monte (Dromiciops gliroides) climbs to lofty heights in the trees. Yet, due to the lack of knowledge about the region’s biodiversity in the forest canopies, no previous records exist documenting such arboreal habits for this creature.

Some tree-climbing researchers are changing that.

Javier Godoy-Güinao and colleagues set motion-sensing camera traps in the tree canopy to capture photographic evidence confirming the high-climbing theories surrounding this miniature mammal. The findings are published in a new study in the Ecological Society of America’s journal Ecosphere.

The monito del monte (Spanish for “little monkey of the bush”, although not a monkey at all) is a small, inarguably cute marsupial that is found solely in the temperate rainforests of Argentina and Chile. It eats mostly insects with some fruit and seeds and nuts, and it also hibernates, which is unusual for marsupials. Females can carry up to five young in a pouch, and a prehensile tail makes it adept at climbing. It is listed as “Near Threatened” by the International Union for Conservation of Nature.

Researchers thought this marsupial may live in the canopy because of its mobility in the vegetation above the forest floor, called the understory. “However,” Godoy-Güinao writes, “all previous studies on D. gliroides have been conducted from the ground, with no documentation of this species’ ability to climb trees, or how high they may reach.” Following the clues from reported sightings, he and his colleagues found the mystery intriguing and decided it worth finding out first hand just how high they climb.

Along with Ivan Díaz, professor in charge of the Laboratory of Canopy Ecology and Biodiversity (CanopyLab) of the Universidad Austral de Chile, and Juan Luis Celis-Diez, professor at P. Universidad Católica de Valparaíso, Godoy-Güinao began studies in 2017 in Bosque Pehuén Park. The park is a protected area owned by the Mar Adentro Foundation, a non-profit dedicated to promoting conservation of and education on biodiversity, and to cultural development in the region.

Researchers climbed high (12-21 m) into the treetops to install the camera traps and patiently waited to capture images of this elusive marsupial. After months of waiting and collecting data, the tiny creatures appeared within the highest camera trap’s view, and it snapped hundreds of photos.

Armed with proof that it is a frequent climber to the highest point of the tallest trees, Godoy-Güinao argues that the role of the monito del monte in the canopy is much more relevant to the biodiversity of the ecosystem than originally thought.

One of its large role lies in seed germination and dispersal. In the treetops of Chilean forests, previous studies by the CanopyLab showed a great variety of air plants such as orchids, bromeliads, lichens, mosses, and ferns that grow within the trees. The monito del monte is a seed disperser of most of these plants; it eats wild fruits and swallows the seeds whole, which then pass through its digestive track and are ready to germinate upon excretion. Given the frequency with which the species visits these high places, it could be the main sower of the plants that make up this vertical garden. Additionally, it is an avid consumer of the insects that attack the foliage of these trees.

Godoy-Güinao hopes that continued study will shed light on the importance of the monito del monte in the treetops, as well learn more about the species. For now, he says, “this evidence suggests that [it] is perhaps the main or only mammal of the region that ventures into the heights of trees, and it can have a very influential role in the biodiversity of the southern South American temperate rainforests.”

South American amphibian saving human lives?


This February 2017 video, recorded in Costa Rica, is about wildlife, especially the Caecilia volcani species of caecilian amphibians.

From the University of Surrey in England:

A South American amphibian could potentially hold the key to curing cirrhosis

December 6, 2017

The unique liver function of a South American amphibian, Siphonops annulatus, could pave the way to finding a cure to the devastating liver condition cirrhosis, a new study published in the Journal of Anatomy reports.

Researchers from the University of Surrey (UK), the Federal University of São Paulo and the Butantan Institute in Brazil used an innovative 3D liver cell examination to explore the liver function of this snake-like amphibian. During an in-depth examination, it was found that the liver of Siphonops annulatus produces blood cells throughout its lifetime and breaks down the protein collagen.

According to Dr Robson Gutierre, a morphologist and leading author of this study, the South American amphibian has very unique liver cells, known as melanomacrophages, which can remove and break down collagen as part of its natural function. In the same species, melanomacrophages also naturally engulf basophils, helping to minimise unwanted inflammation and reduce the scar tissue which can lead to cirrhosis.

Cirrhosis occurs in response to damage to the liver. Chronic alcoholism, hepatitis or other harmful substances can promote the response of self-repair in the liver, mainly represented as a high production of collagen and scar formation (fibrosis). As cirrhosis progresses, liver functions such as detoxification and cleaning of blood, among others, become difficult.

Several treatment strategies for cirrhosis have been tried throughout the world, such as delaying or removing the underlying stimulus that causes scars to form. Other treatments have looked at the degradation and/or removal of collagen.

Co-author Dr Augusto Coppi, lecturer in Veterinary Anatomy and Stereologist at the University of Surrey, said: “The liver function of this amphibian, Siphonops annulatus, may provide us with a unique opportunity to solve one of the most devastating illnesses of the liver.

“We do need further in-depth investigations into how this discovery could be translated into humans, but it may have the potential to alter how we view and treat this disease. We are constantly amazed by nature, and this particular and not-well-studied species of amphibian could help us find a way to stop or even reverse liver cirrhosis.”

Dr Robson Gutierre from the Federal University of São Paulo said: “The ability this species has to break down its natural defences could also provide insight into immunity tolerance, a mechanism by which the liver can minimise unwanted inflammations. Immunity tolerance can be studied in this species because they produce pro-inflammatory cells in the hematopoietic liver throughout its whole life, without developing chronic inflammations.”

Liver cirrhosis must be diagnosed early and the cause treated, but damage is rarely reversed. In the late stages, cirrhosis is life threatening. Every year more than 4,000 people in the UK die from cirrhosis and an estimated 700 people have to have a liver transplant each year to survive.

Researchers will continue to explore how this could be translated into humans.