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Ancient eggshells unlock discovery of extinct elephant bird lineage – Phys.org

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hat a whole Aepyornis egg would have looked like when freshly laid, seen in a market near the town of Toliara on the southwest coast of Madagascar. Credit: Gifford Miller

More than 1,200 years ago, flightless elephant birds roamed the island of Madagascar and laid eggs bigger than footballs. While these ostrich-like giants are now extinct, new research from CU Boulder and Curtin University in Australia reveals that their eggshell remnants hold valuable clues about their time on Earth.

Published today in Nature Communications, the study describes the discovery of a previously unknown, separate lineage of elephant bird that roamed the wet, forested landscapes on the northeastern side of Madagascar—a discovery made without access to any skeletal remains.

It’s the first time that a new lineage of elephant bird has been identified from ancient eggshells alone, a pioneering achievement which will allow scientists to learn more about the diversity of birds that once roamed the world and why so many have since gone extinct in the past 10,000 years.

“This is the first time a taxonomic identification has been derived from an elephant bird eggshell and it opens up a field that nobody would have thought about before,” said paper co-author Gifford Miller, distinguished professor of geological sciences and faculty fellow at the Institute of Arctic and Alpine Research (INSTAAR) at CU Boulder. “Here may be another way of looking into the past and asking, ‘Was there more diversity in birds than we’re aware of?'”

Akin to a small continent, Madagascar has been separated from Africa and neighboring continents by deep ocean water for at least 60 million years. This geology has allowed evolution to run wild, producing lemurs, elephant birds, and all kinds of animals that exist nowhere else on the planet.

For the Polynesian peoples who arrived here around 2,000 years ago, the largest of the elephant birds, Aepyornis, was a feathery terror to behold: at more than 9 feet tall, weighing more than 1,500 pounds each, and outfitted with a pointy beak and deadly foot talons, it was Madagascar’s largest land animal.

Due to limited —and the fact that bone DNA degrades quickly in warm, humid areas—it was not known until recently where the birds fit into the . The most scientists knew was that they were part of the flightless ratite family, a genetic sister to the New Zealand kiwi, the world’s smallest living ratite.

Ancient eggshell DNA, however, has confirmed not only where the elephant birds sit in this tree, but revealed more about the diversity within the lineage.

“While we found that there were fewer species living in southern Madagascar at the time of their extinction, we also uncovered novel diversity from Madagascar’s far north,” said lead author Alicia Grealy, who conducted this research for her doctoral thesis at Curtin University in Australia. “These findings are an important step forward in understanding the complex history of these enigmatic birds. There’s surprisingly a lot to discover from eggshell.”

<div data-thumb="https://scx1.b-cdn.net/csz/news/tmb/2023/ancient-eggshells-unlo.jpg" data-src="https://scx2.b-cdn.net/gfx/news/hires/2023/ancient-eggshells-unlo.jpg" data-sub-html="Collection and characterization of elephant bird eggshell morphotypes. a Map of Madagascar depicting the geographic location of eggshell samples collected (small circles) and analyzed (larger circles with a border). Samples with genetic data are represented by their ID# and the thickness of the sample is proportional to the icon represented to its right. The location of fossil specimens of aepyornithids (diamonds) and mullerornithids (squares) are shown (Fig.&nbsp;1c; see Supplementary Data&nbsp;1 for locality data and references). Specimens for which DNA data were available are colored yellow, including the four previously published genomes retrieved from bone specimens. Superscripts beside specimens refer to the literature that previously published genetic data for these specimens. Simplified topography of the landscape is shown with rivers represented by fine lines (adapted from https://commons.wikimedia.org/wiki/File:Madagascar_rivers.svg under CC BY-SA 3.0, https://creativecommons.org/licenses/by-sa/3.0/deed.en; river names omitted) and biomes represented by shades of gray (adapted from Brown et al.93 under CC BY 4.0). b The distribution of eggshell thicknesses derived from the total number of eggshells collected across the north and south of Madagascar. Width of eggshell silhouettes are scaled to represent the mean thickness for the morphotype, and are positioned over the X-axis at the mean thickness; the width of the colored bars depict two standard deviations either side of the mean. c Taxonomic revisions for elephant birds with superscripts cross-referencing the original author of the taxonomic name94,95,96,97,98,99,100. Source data for this figure can be found in Supplementary Data&nbsp;1–4. Credit: Nature Communications (2023). DOI: 10.1038/s41467-023-36405-3″>
Collection and characterization of elephant bird eggshell morphotypes. a Map of Madagascar depicting the geographic location of eggshell samples collected (small circles) and analyzed (larger circles with a border). Samples with genetic data are represented by their ID# and the thickness of the sample is proportional to the icon represented to its right. The location of fossil specimens of aepyornithids (diamonds) and mullerornithids (squares) are shown (Fig. 1c; see Supplementary Data 1 for locality data and references). Specimens for which DNA data were available are colored yellow, including the four previously published genomes retrieved from bone specimens. Superscripts beside specimens refer to the literature that previously published genetic data for these specimens. Simplified topography of the landscape is shown with rivers represented by fine lines (adapted from https://commons.wikimedia.org/wiki/File:Madagascar_rivers.svg under CC BY-SA 3.0, https://creativecommons.org/licenses/by-sa/3.0/deed.en; river names omitted) and biomes represented by shades of gray (adapted from Brown et al.93 under CC BY 4.0). b The distribution of eggshell thicknesses derived from the total number of eggshells collected across the north and south of Madagascar. Width of eggshell silhouettes are scaled to represent the mean thickness for the morphotype, and are positioned over the X-axis at the mean thickness; the width of the colored bars depict two standard deviations either side of the mean. c Taxonomic revisions for elephant birds with superscripts cross-referencing the original author of the taxonomic name94,95,96,97,98,99,100. Source data for this figure can be found in Supplementary Data 1–4. Credit: Nature Communications (2023). DOI: 10.1038/s41467-023-36405-3

An eggshell-ent idea

Miller has analyzed eggshell remains in Australia and around the world for more than 20 years—one of few scientists who study these fragments. So, in 2005, when he was awarded $25,000 as part of the Geological Society of America’s Easterbrook Distinguished Scientist Award, Miller gathered a small team to study the evolutionarily elusive elephant bird.

The team initially set out in 2006 to collect elephant bird eggshells from the dry, southern half of the island. When an unaffiliated researcher used to solve this evolutionary mystery before they could, Miller and Grealy’s team turned their attention to the wet, forested north half of the island, hoping to better understand the bird in a different biome.

Using , the team scouted locations where winds had blown the sands away and exposed ancient eggshells. No birds of any similar size currently live on the island, so the cracked pieces are easily recognizable to the naked eye. After the team traversed the island and gathered more than 960 ancient eggshell fragments from 291 locations, the challenging work began: analyzing the ancient DNA.

Due to their chemical makeup, skeletons can be “leaky” with their DNA, making them less ideal for this kind of work. In comparison, the physical chemistry of these thick eggshells locks in its organic matter for up to 10,000 years and protects its DNA like it did the baby bird that once grew inside of it. This means it can be rather difficult to extract for analysis.

Another problem is finding long enough strands of DNA to analyze, as ancient DNA is often degraded. As a result, the scientists pieced together the shorter fragments in a kind of “genetic jigsaw puzzle”—with no idea it would lead them to discover a new type of elephant bird.

“Science often advances in obscure pathways. You don’t always find what you were looking for,” said Miller, director for the Center for Geochemical Analysis of the Global Environment (GAGE) at CU Boulder. “And it’s much more interesting to find what you didn’t know you were looking for.”

The human or the egg?

Miller studies the “Quaternary,” the most recent geological period in Earth’s history and when humans first appeared on the landscape. When humans appeared, he said, often large animals went extinct—but scientists still don’t know why the elephant bird was one of them.

“What is it that early humans are doing that’s resulting in extinction of big animals, especially? This is a debate that’s been going on for my whole life,” said Miller, whose career now spans five decades.

If geologists, archaeologists and biologists are able to gather and date more eggshell fragments from around the world, however, Miller and Grealy’s pioneering work in the field of eggshell DNA science could lead to a better understanding of why large animals like the elephant bird went extinct after the arrival of humans.

“With lots of little contributions from a whole bunch of people, you actually can solve some interesting questions,” said Miller. “This might open up a new way of looking at things.”

More information:
Alicia Grealy et al, Molecular exploration of fossil eggshell uncovers hidden lineage of giant extinct bird, Nature Communications (2023). DOI: 10.1038/s41467-023-36405-3

Citation:
Ancient eggshells unlock discovery of extinct elephant bird lineage (2023, February 28)
retrieved 28 February 2023
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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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B.C. sets up a panel on bear deaths, will review conservation officer training

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VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.

Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”

Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.

“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.

B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.

Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.

Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.

Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.

“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”

Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”

“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.

Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.

“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.

This report by The Canadian Press was first published Sept. 9, 2024.

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Asteroid Apophis will visit Earth in 2029, and this European satellite will be along for the ride

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The European Space Agency is fast-tracking a new mission called Ramses, which will fly to near-Earth asteroid 99942 Apophis and join the space rock in 2029 when it comes very close to our planet — closer even than the region where geosynchronous satellites sit.

Ramses is short for Rapid Apophis Mission for Space Safety and, as its name suggests, is the next phase in humanity’s efforts to learn more about near-Earth asteroids (NEOs) and how we might deflect them should one ever be discovered on a collision course with planet Earth.

In order to launch in time to rendezvous with Apophis in February 2029, scientists at the European Space Agency have been given permission to start planning Ramses even before the multinational space agency officially adopts the mission. The sanctioning and appropriation of funding for the Ramses mission will hopefully take place at ESA’s Ministerial Council meeting (involving representatives from each of ESA’s member states) in November of 2025. To arrive at Apophis in February 2029, launch would have to take place in April 2028, the agency says.

This is a big deal because large asteroids don’t come this close to Earth very often. It is thus scientifically precious that, on April 13, 2029, Apophis will pass within 19,794 miles (31,860 kilometers) of Earth. For comparison, geosynchronous orbit is 22,236 miles (35,786 km) above Earth’s surface. Such close fly-bys by asteroids hundreds of meters across (Apophis is about 1,230 feet, or 375 meters, across) only occur on average once every 5,000 to 10,000 years. Miss this one, and we’ve got a long time to wait for the next.

When Apophis was discovered in 2004, it was for a short time the most dangerous asteroid known, being classified as having the potential to impact with Earth possibly in 2029, 2036, or 2068. Should an asteroid of its size strike Earth, it could gouge out a crater several kilometers across and devastate a country with shock waves, flash heating and earth tremors. If it crashed down in the ocean, it could send a towering tsunami to devastate coastlines in multiple countries.

Over time, as our knowledge of Apophis’ orbit became more refined, however, the risk of impact  greatly went down. Radar observations of the asteroid in March of 2021 reduced the uncertainty in Apophis’ orbit from hundreds of kilometers to just a few kilometers, finally removing any lingering worries about an impact — at least for the next 100 years. (Beyond 100 years, asteroid orbits can become too unpredictable to plot with any accuracy, but there’s currently no suggestion that an impact will occur after 100 years.) So, Earth is expected to be perfectly safe in 2029 when Apophis comes through. Still, scientists want to see how Apophis responds by coming so close to Earth and entering our planet’s gravitational field.

“There is still so much we have yet to learn about asteroids but, until now, we have had to travel deep into the solar system to study them and perform experiments ourselves to interact with their surface,” said Patrick Michel, who is the Director of Research at CNRS at Observatoire de la Côte d’Azur in Nice, France, in a statement. “Nature is bringing one to us and conducting the experiment itself. All we need to do is watch as Apophis is stretched and squeezed by strong tidal forces that may trigger landslides and other disturbances and reveal new material from beneath the surface.”

The Goldstone radar’s imagery of asteroid 99942 Apophis as it made its closest approach to Earth, in March 2021. (Image credit: NASA/JPL–Caltech/NSF/AUI/GBO)

By arriving at Apophis before the asteroid’s close encounter with Earth, and sticking with it throughout the flyby and beyond, Ramses will be in prime position to conduct before-and-after surveys to see how Apophis reacts to Earth. By looking for disturbances Earth’s gravitational tidal forces trigger on the asteroid’s surface, Ramses will be able to learn about Apophis’ internal structure, density, porosity and composition, all of which are characteristics that we would need to first understand before considering how best to deflect a similar asteroid were one ever found to be on a collision course with our world.

Besides assisting in protecting Earth, learning about Apophis will give scientists further insights into how similar asteroids formed in the early solar system, and, in the process, how  planets (including Earth) formed out of the same material.

One way we already know Earth will affect Apophis is by changing its orbit. Currently, Apophis is categorized as an Aten-type asteroid, which is what we call the class of near-Earth objects that have a shorter orbit around the sun than Earth does. Apophis currently gets as far as 0.92 astronomical units (137.6 million km, or 85.5 million miles) from the sun. However, our planet will give Apophis a gravitational nudge that will enlarge its orbit to 1.1 astronomical units (164.6 million km, or 102 million miles), such that its orbital period becomes longer than Earth’s.

It will then be classed as an Apollo-type asteroid.

Ramses won’t be alone in tracking Apophis. NASA has repurposed their OSIRIS-REx mission, which returned a sample from another near-Earth asteroid, 101955 Bennu, in 2023. However, the spacecraft, renamed OSIRIS-APEX (Apophis Explorer), won’t arrive at the asteroid until April 23, 2029, ten days after the close encounter with Earth. OSIRIS-APEX will initially perform a flyby of Apophis at a distance of about 2,500 miles (4,000 km) from the object, then return in June that year to settle into orbit around Apophis for an 18-month mission.

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Furthermore, the European Space Agency still plans on launching its Hera spacecraft in October 2024 to follow-up on the DART mission to the double asteroid Didymos and Dimorphos. DART impacted the latter in a test of kinetic impactor capabilities for potentially changing a hazardous asteroid’s orbit around our planet. Hera will survey the binary asteroid system and observe the crater made by DART’s sacrifice to gain a better understanding of Dimorphos’ structure and composition post-impact, so that we can place the results in context.

The more near-Earth asteroids like Dimorphos and Apophis that we study, the greater that context becomes. Perhaps, one day, the understanding that we have gained from these missions will indeed save our planet.

 

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