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New prehistoric plant discovery highlights the unexpected diversity of non-flowering plants – The Conversation

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The renowned Apple Bay fossil locality of northern Vancouver Island is helping us reimagine seed plant diversity in the Early Cretaceous, the last of three geologic periods comprising the Mesozoic Era.

Until recently, it was assumed that most major lineages of seed plants had been recognized in the fossil record. Their evolution and relationships to one another are still being debated, but few botanists believed that we might still be missing wide swathes of vascular plant diversity.

Using fossils from this site, my colleagues (paleobotanists Gar Rothwell and Ruth Stockey) and I have been challenging the assumption that the plant fossil record is largely complete. Our recent discovery of a new genus of non-flowering seed plants illustrates that researchers’ understanding of seed plant diversity in the Cretaceous is by no means complete.

Exceptionally detailed fossilization

In Apple Bay, sandstone and siltstone beds tilt gently up, variably exposed with every falling tide, and giving few clues as to their scientific significance. This site is a konservat lagerstätte: a fossil locality with exceptional preservation.

During the Early Cretaceous (about 136 million years ago), seasonal storms and flooding events swept vegetation out into a marine basin. Plant debris rapidly settled and fossilized at a cellular level of detail. This type of fossilization is called permineralization.

Permineralized plants offer a wealth of anatomical information, enabling us to ascertain features of plant development, organography (the arrangement of plant organs) and reproduction — data critical for understanding plant evolution. In the two decades we’ve been studying Apple Bay, it has become apparent that this site contains the most comprehensive record of terrestrial vegetation immediately prior to the evolution and radiation of angiosperms (flowering plants).

Flower power

A mere five to 10 million years after the Apple Bay flora settled into marine sediments, angiosperms were becoming abundant in the fossil record. Through the Late Cretaceous, they came to dominate terrestrial landscapes.

Prevailing narratives in plant biology suggest angiosperms out-competed other seed plants. Perhaps angiosperms were more adaptive to changing climate; used nutrients more effectively; or gymnosperms — non-flowering seed plants — were already in decline by the Early Cretaceous, enabling angiosperms to opportunistically occupy newly available niche space.

Welwitschia mirabilis, a type of non-flowering seed plant, in the Namibian desert.
(Shutterstock)

The vast majority of seed plants that have ever lived are now extinct. The gymnosperms that are still alive are themselves relics of a much greater fossil diversity, and many major lineages of seed plants are known only from the fossil record. The permineralized plants of Apple Bay demonstrate that seed plants were even more diverse throughout the Cretaceous than botanists had previously realized.

Gymnosperms are well-represented in the Apple Bay flora. They include conifers and gnetophytes, which still have living exemplars like Welwitschia. They also include bennettitalean and doylealean plants, which represent wholly extinct orders. Indeed, the extinct Doyleales were first described from Apple Bay in 2009, and have subsequently been found in Mongolia as well.

Plant discovery

The new plant, Xadzigacalix quatsinoensis, probably also represents yet another order of extinct plants. The name is a nod to Kwak̓wala-speaking First Nations — the Apple Bay locality occurs within traditional and unceded territory of the Quatsino First Nation. Xadzigacalix derives from xa̱dziga, a Kwak̓wala word for plant resin, and calix, which is Latin for chalice. The name reflects the resinous, fleshy cupule that surrounds and protected the seeds of the Xadzigacalix plant.

The seeds of this plant have complex three-layered seed coats and were produced at the tip of a woody stem. A cupule encloses most of the seed, except for a narrow tube through which the embryo would have been pollinated. This organography, along with anatomical features like vascular tissue that are observable at a cellular level, constitute a novel combination of features not found in any other lineage of plants.

It’s not yet clear which group of seed plants actually gave rise to the angiosperms. Xadzigacalix likely represents a new order of seed plants, perhaps distantly related to gnetophytes or angiosperms. While research in plant molecular systematics (a discipline that uses genetic data to understand plant relatioships) has resolved most evolutionary relationships within flowering plants, their origins and nearest relatives remain mysterious.

a cross section of a fossilised plant structure

A fossilized seed and cupule of Xadzigacalix quatsinoensis.
(Az Klymiuk), Author provided

Part of this problem is that the group of seed plants most closely related to angiosperms is almost certainly extinct. Several major groups of cupulate Mesozoic gymnosperms, sometimes called corystosperms or seed ferns, have been suggested as possible relatives of angiosperms. The Xadzigacalix plant is yet another possible contender to the broader “family tree” of flowering plants.

Perplexing origins

Our assessment of the evolutionary context of the Xadzigacalix plant led us to re-evaluate the other groups of plants frequently suggested as angiosperm relatives. Throughout the Mesozoic, many seed plants “experimented” with an array of different seed-enclosing structures.

We examined whether these cupulate structures are developmentally derived from leaf or shoot tissues. Across all Mesozoic seed plants, cupules appear to be a case of evolutionary convergence, where different seed plants independently evolved similar features. It’s by no means clear if the cupules of any group are genuinely similar to the carpels — the female organs — of flowering plants.

I believe the reason angiosperm origins remain perplexing is that we still stand to discover the entirety of Mesozoic plant diversity. Our discovery of Xadzigacalix hints at how much there is is left to learn.

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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.

The Canadian Press. All rights reserved.

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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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Asteroid Apophis

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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