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The Lost World of the Maya is Finally Emerging From the Jungle

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Thomas Garrison pauses in the middle of the jungle.


“That’s the causeway right there,” he says, pointing into a random patch of
greenery in the Guatemalan lowlands.


I squint, trying to make out features in the tangled rainforest
undergrowth. There’s a small lump, rising no more than a foot or two from
the forest floor.


The Ithaca College archaeologist has spotted the buried remnants of a Maya
road, a ribbon of limestone that once cut through the wrinkled landscape.
We’re a full day’s walk from civilization, standing in the remains of a
once-populous kingdom. The road before us is just one piece of a vast
network leading to terraced fields, reservoirs, defensive fortifications
and more, all sprawling invisibly throughout the forest.


In the 1,000-plus years since the Maya society collapsed, the jungle has
returned with a vengeance. A tide of flora has swallowed up roads and
temples, turning stone structures into lumps and mounds indistinguishable
from the natural topography.


Garrison, an expert at picking out buried structures, had walked right by
this road for years, never knowing it was there. But now, a revolutionary
technology called lidar is giving archaeologists a God’s-eye view of the
rainforest — and what’s buried beneath.


Lidar, which stands for light detection and ranging, bathes the jungle
canopy in a stream of laser beams delivered from planes flying above. As
the light bounces back, it creates a precise map of surface contours
beneath the forest canopy.


Back in camp, Garrison pulls up the data on his laptop. Maya ruins leap
from the featureless jungle, giving new meaning to the landscape that
surrounds us. The researchers’ base shows up as a small huddle of
buildings; surrounding it, hundreds of Maya structures stipple the ground
in every direction. Some Garrison knew about — the majority, however, are
brand new. To him, at least.


Back in 2016, Garrison and a group of archaeologists organized a sweeping
lidar survey of the heart of Maya civilization, once centered here in the
Guatemalan lowlands. Their scans covered 800 square miles across the Petén
region, which covers much of Guatemala’s northern half. It’s just a
fraction of the former Maya territory, yet lidar revealed some 60,000
previously unknown structures.


Now, researchers can comprehend the full scale of this ancient
civilization, from vastly expanded trade and agriculture to surprising
military sophistication. After decades of digging, new and exciting
dimensions of Maya society are finally coming to light.

Peephole to Panorama

Over a thousand years ago, the Maya dominated this environment. They
emerged around 1000 B.C. and, over the next millennia, rose to become the
pre-eminent Mesoamerican civilization.


Millions of people lived in the forest, members of a loose alliance of
interconnected city-states. The Maya developed a system of writing, as well
as a calendar system and sophisticated astronomical charts. In a world
without metal, they built towering temples in cities like Tikal and Chichén
Itzá, as well as roads, reservoirs, irrigation networks and terraced
fields. Their civilization spanned thousands of square miles of jungle
across Central America.



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Ecology

Pumped Milk Gives Infants Different Bacteria Than Breastfeeding, Study Says

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baby feeding milk bottle

(Credit: Africa Studio/Shutterstock)

Mother’s milk provides sustenance for babies. Now researchers find pumped breast milk exposes newborns to more disease-causing bacteria than milk directly from the breast. The discovery suggests breastfeeding practices could shift the makeup of microorganisms in breast milk and infants’ digestive systems.

“We were surprised that the method of feeding was the most consistent factor associated with milk microbiota composition,” said Meghan Azad, a medical geneticist at the Children’s Hospital Research Institute of Manitoba in Canada, who led the new research.

Mighty Milk

Once considered sterile, researchers now know breast milk is full of bacteria. The microbes are thought to help set up infants’ digestive tracts with an ecosystem of microorganisms that will aid the growing human’s digestive and immune systems. Azad and her team were initially curious about this collection of bacteria in infants known as the infant gut microbiome. In an earlier study, they found breastfeeding affected babies’ gut bacteria the most. So, in the new research, the scientists probed the microbes in breast milk.

The researchers checked out the microbes in breast milk from nearly 400 nursing mothers and their three to four month old babies. The mommy-baby pairs are a part of a Canadian Healthy Infant Longitudinal Development birth cohort study known as the CHILD study, a long-term project looking to find the source of pediatric allergies. The researchers also looked at other elements — maternal age, smoking status and the microbes in babies mouths, to name a few — that could affect what bacteria are in breast milk.

Pumping Problem

The microbes in breast milk varied drastically between mothers, the researchers found, and both mom and baby mold the milk microbiome.

“Our results suggest that the infant’s oral bacteria are important in shaping the milk microbiota,” said Shirin Moossavi, a medical microbiology student in Azad’s lab, who authored the research.

But the biggest factor was whether babies received breast milk straight from the nipple or from a bottle. A family of bacteria that includes E. coli and salmonella were more abundant in pumped breast milk than direct breast milk, the researchers reported Wednesday in the journal Cell Host & Microbe.

“It is only in recent years that we have started to understand that there might be differences between direct nursing compared to feeding pumped milk,” Azad said.

“In the future, when we understand the mechanisms better, we might be able to provide recommendations about pump apparatus cleaning and milk storage to minimize the impact on the milk microbiota,” Moossavi added.

But no matter the delivery mode, “overall, breast milk is the best for the infant,” the researchers said.



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NASA Wants to Return to the Moon as Early as This Year

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NASA moon

NASA has big plans for returning to the moon, but private companies will do much of the work. (Credit: NASA)

In November, NASA tapped nine private spaceflight companies who will be allowed to bid on upcoming projects. Yesterday, they elaborated on what those projects would be during an industry forum. Starting as early as this year, NASA hopes to send commercial landers to the lunar surface as the first step toward returning to the moon, this time for good.

Long Lunar To-Do List

There’s a lot of work to be done before permanent or long-term lunar activities can begin. The first tasks will be to practice launching and landing on the moon, as well as answering questions about its surface. There’s plenty of technology NASA wants to see established on the ground before humans are sent back to the moon – and a lot of it is meant to stand in for future Mars settlement as well.

Some of that technology has to do with a recent buzzword among the space settlement community: in-situ resource utilization, or ISRU. This means using materials and resources already available on the moon and, one day, Mars, rather than carting all our resources with us, as has been standard for space missions. This most commonly means using solar power for energy. On the moon, it will also mean extracting water, which can be used for drinking or to power rockets. Both the hydrogen and oxygen that make up water are powerful fuel materials.

So commercial lunar partners will work on how to mine and recycle resources on the moon and make them available for future mission use. They will test habitation for future crewed missions. They’ll prove that they can collect materials from the lunar surface and return them to space or Earth. And they’ll establish communication networks between robots on the moon’s surface, way stations in lunar orbit, and mission control on Earth.

All these commercial endeavors would also need to integrate with NASA’s planned Lunar Gateway. This would be a space station in orbit around the moon that would serve as Grand Central Station for robotic or crewed missions to the lunar surface, or even for deep space missions. NASA hopes to open the Gateway by 2026, with the first power and propulsion elements entering orbit in 2022.



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Climate Change Hearings Signal Congress Is Willing to Address the Issue Again

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climate change

(credit: Roschetzky Photography/Shutterstock)

Climate change is real. It’s happening now. And it presents significant problems for the U.S. across multiple facets of society, according to a panel of climate and policy experts that testified before the House Science, Space and Technology Committee Wednesday in Washington, D.C.

The testimonials were part of the House Science Committee’s first full hearing of the 116th Congress and one of only a handful in the last eight years to address climate change. But that’s about to change. In her opening remarks, House Science Committee Chairwoman Eddie Bernice Johnson (D-TX) said Wednesday’s hearing will be the first of multiple hearings on climate change in the near future.

“Climate change is not just an environmental challenge,” said Robert Kopp, a climate scientist at Rutgers University in New Brunswick, New Jersey, during his testimony. “It’s an economic challenge, an infrastructure challenge, a public health challenge and a national security challenge.”

Carbon Cuts

For the most part, House representatives were in agreement with the panel that climate change is real and harming not only the environment but the economy and Americans. During the nearly two and half hours of questions that followed the researchers’ testimonies, representatives asked the scientists to identify priorities and sought their suggestions for solutions.

“Human emissions of CO2 must be brought as close to zero as possible with any continued emissions of CO2 balanced by human removal of carbon dioxide from the atmosphere,” said Kopp, who suggested expanding forests and using new, but little-tested technologies as a start. “The faster we reduce emissions, the less severe the effects and the lower the risk of unwelcome surprises,” he added.

Cities, states and a number of companies are already taking action by adopting emission reduction targets, but Kopp says these efforts need to grow dramatically and rapidly to effectively manage climate risk.

But Joseph Majkut, a policy expert with the Niskanen Center, a non-partisan think tank based in Washington, D.C., who also testified, acknowledged, “That’s a challenging thing to do.”

“To even get close, we’ll need significant innovation in low-carbon technology, finance and market design in order to be able to provide reliable, affordable and globally accessible low carbon energy,” Majkut said.

Majkut projected that to reach any temperature target, much less the 1.5 degrees C (2.7 degrees F) of warming goal set by the IPCC, would require carbon capture and storage of fossil fuels as well as carbon removal technologies in conjunction with renewable energy and storage solutions. He then advocated for research into alternatives to reducing global emissions, such as geoengineering technologies that would offset greenhouse gas production.

The scientists’ recommendations align with many facets of the Green New Deal Rep. Alexandria Ocasio-Cortex (D-NY) and Sen. Ed Markey (D-MA) recently proposed. The legislation calls for a massive policy shift that bolsters the U.S. economy and cuts greenhouse gas emissions to zero. Like the solutions Majkut outlined for the House Science Committee, the Green New Deal lists expanding and upgrading renewable energy sources, removing greenhouse gases from the atmosphere and increasing carbon storage as ways to achieve its goal.

Rep. Ralph Norman (R-SC) and others raised concerns about the cost of such an initiative, asking “If the Green New Deal were implemented immediately, wouldn’t it devastate our economy?” But, says Majkut, reducing CO2 associated with economic activity is “one of the cheapest elements” of the bill.

Adaptive Measures

The scientists testifying before the House also recommended prioritizing research into the ways society might adapt to climate change and called on federal support for studies of how climate change will affect communities, a research topic Kristie Ebi, an epidemiologist at the University of Washington in Seattle, is already looking into.

Ebi, another scientist to testify at the hearing, investigates how climate change affects human health. Researchers have discovered Americans are already suffering and dying from climate change and the impacts will likely only get worse.

“Risk from vector-borne diseases such as malaria, Dengue fever and Lyme disease are projected to increase with warming from 1.5 to 2 C (2.7 to 3.6 F) including potential shifts in their geographic range to areas previously unexposed to these diseases,” Ebi said. “Further, our healthcare infrastructure is vulnerable to extreme events with, for example, many hospitals and healthcare clinics located in coastal regions subject to flooding.”

Yet, there are achievable ways to alleviate the projected risks and costs associated with climate change’s impacts on communities, Ebi said, such as “developing early notification response plans for extreme heat … and incorporating climate projections into emergency preparedness and disaster risk management initiatives.”

“These steps can protect health now and provide a basis for effective adaptation to our future climate,” she added.

And if the world does not slow the rise of greenhouse gas emissions, Americans’ health and the U.S. economy will suffer because of impacts associated with mortality and the ability of people to work outdoors, scientists say. More extreme weather events will also affect human health and the economy.

“We know that in 2018, the losses due to extreme weather were roughly $160 billion just to the U.S.,” said Jennifer Francis, an atmospheric scientists at the Woods Hole Research Center in Falmouth, Massachusetts, during her testimony. “But what keeps me up at night is thinking about my own daughter and the world she will face if we do nothing.”



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