It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Saturday, September 09, 2023
Urban development 'nibbling' away at Metro Vancouver's sensitive ecosystems: report
Metro Vancouver's urban core is losing hundreds of hectares of sensitive ecosystems annually as regional planners attempt to increase protected lands by 25 per cent, by 2050.
Graeme Wood about 12 hours agoBurns Bog in Delta.Sandor Gyarmati/Delta Optimist
Metro Vancouver continues to lose hundreds of hectares of sensitive ecosystems per each year while simultaneously seeking to increase the amount of protected land by 2050, a new report to the regional government’s board of directors shows.
Metro Vancouver senior planner Laurie Bates-Frymel reported that the region, from Lions Bay and eastward to Maple Ridge and Langley, contains 176,429 hectares of “sensitive and modified” ecosystem, which largely includes the North Shore’s forests and the Fraser River estuary, including Boundary Bay and Roberts Bank.
Since 2009 the region has lost 2,500 hectares, 1,800 of which came within the urban core, which only accounts for 33,554 hectares, comprising largely of grasslands, streams and large parks — such as Burns Bog, the UBC Endowment Lands and Stanley Park — intertwined with human infrastructure.
“The speed and scale of this ongoing loss is concerning for many reasons,” including loss of flood protection, carbon storage, urban heat mitigation and mental and physical health benefits, said Bates-Frymel.
The losses, however, do appear to be abating, said Bates-Frymel.
The region lost just 900 hectares between 2014 and 2020, whereas it lost 1,600 between 2009 and 2014 — just over the size of New Westminster.
“That’s good news. We’re slowing down the loss of ecosystems,” said Bates-Frymel.
More recently, the region lost 700 hectares of forest, 400 hectares of which were in the urban core.
“The nature of ecosystem loss observed over the last five years ranges widely, from the clearing of large, high-quality ecosystems, to small, disturbed remnant patches,” Bates-Frymel’s report states.
“Even smaller losses, or nibbling, can add up to large losses over the long-term,” Bates-Frymel told the board.
There are many causes of ecosystem loss, she noted: 34 per cent to logging; 23 per cent to agriculture; 16 per cent residential development; 10 per cent mowing and clearing; and six per cent industrial development, most notably.
“There’s definitely trade-offs,” said Bates-Frymel, noting the most permanent losses are via human development, as agriculture and cleared forests can often return back to a sensitive ecosystem.
While these lands are being lost, Metro Vancouver is aiming to increase the amount of permanently protected sensitive ecosystems, from 40 per cent of the land mass to 50 per cent by 2050.
Bates-Frymel said the process involves park acquisition by Metro Vancouver, municipalities, First Nations and the provincial government; but also conservation groups and private citizens.
Bates-Frymel’s report titled Sensitive Ecosystem Inventory Update 2014-2020 Change Summary was received unanimously by the board on Sep. 7.
ONTARIO
Hundreds of Peel Region education workers terminated days before school year start, union says
The Peel District School Board said many terminated workers were not in compliance with conditions for employment. Global News
Almost 500 education workers, including educational assistants, were terminated by the Peel District School Board late last week, the union representing the workers says.
In an email to Global News late Friday evening, Melody Hurtusbie, president of the Ontario Public Service Employees Union (OPSEU) Local 2100, said over 300 educational assistants and over 100 early childhood educators were terminated last week.
According to Hurtusbie, the terminated employees were notified at 5:45 p.m. on Sept. 1, before the Labour Day long weekend.
“These actions wreaked havoc on my members, causing uncertainly and anxiety,” she said. “I heard from many of them saying that they had picked up long-term occasional jobs beginning on the first day of the school year and were now unsure if they were permitted to work.”
In a statement emailed to Global News on Friday, the PDSB said that during the COVID-19 pandemic it offered “flexibility to casual EAs, by way of extending the number of days required to work, beyond the collective agreement requirements.”
“Such was done recognizing the shifting landcape during the height of the global COVID-19 pandemic,” the statement said.
The board said, however, in the “present context” schools have returned to in-person learning, adding that “all school boards have been impacted by high absenteeism rates.”
According to the board, it discovered some EAs on the casual list who had not worked for the PDSB at all, had not met the minimum working days requirement in the collective agreement, or who were “non-compliant” with the annual obligation to disclose their criminal background.
“Given the increase in operational requirement to cover absences, staff who did not meet their obligations in the three categories above, in particular those who had not worked for the school board at all were removed from the list,” the statement said.
Under the collective agreement, casual employees are required to work at least 40 days, while retirees must work at least 20.
However, Hurtusbie said the union requested a moratoruim on the article in the collective agreement regarding the work-day requirements, saying schools are “short staffed and have low absence fill rates and need as many casual staff as possible.”
“We are already short staffed and with additional budget cuts and funding shortages it has created a crisis of understaffing,” Hurtusbie said in the email.
She said even without the casual staff, “there aren’t enough EAs to support the students in schools.”
However, the board said it has “incrementally increased” its hiring efforts to be year-round and said it has added “approximately 500 EAs to the casual list since the last school year.”
What’s more, the Ministry of Education said the PDSB reported around 2,260 full-time equivalent EAs for the 2023-2024 year, and the addition of 500 EAs to the list since last year.
The ministry also said the school board is projected to receive over $1.8 billion in base funding through the Grants for Student Needs (GSN) for the new school year, which includes an increase of over $32 million since 2023-24, as well as $227 million through the special education funding.
Surprise: Donald Trump’s Border Wall That Mexico Never Paid for Caused “Irreparable Harm” to the Environment, Endangered Species, and Cultural Sites
An “entire mountainside” is said to be in danger of collapse thanks to construction done during the Trump administration.
BESS LEVIN
VANITY FAIR SEPTEMBER 8, 2023 JOSHUA ROBERTS/GETTY IMAGES
According to a new report released by the Government Accountability Office this week, the roughly 450 miles of wall that went up during the Trump administration harmed everything from water to endangered species to Native American cultural sites. Monument Hill, for example, a memorial in Arizona used for religious ceremonies that remains important to a number of Indigenous communities, was “irreparably damaged when contractors used explosives to clear the way for expanding an existing patrol road.” Similarly, Tohono O’odham Nation officials reported to the GAO that a sacred burial site near Quitobaquito Springs was destroyed when contractors cleared a large area there.
Elsewhere, the report notes that:
Construction disrupted water flows, and in turn, exacerbated flooding.
The clearing of land for the wall “damaged native vegetation.”
Clearing land without reseeding it “allowed invasive species to take root.”
As a result of the construction work, some ponds in the San Bernardino National Wildlife Refuge in Arizona “are now void of water, which makes it difficult to maintain water levels in other ponds that have threatened and endangered fish species.”
“The barrier system has…substantially elevated the risks of the ocelot’s extinction in the US.”
A large construction staging area erected in the Pajarito Mountains in Arizona caused silt to drain “down the side of the mountain and, according to Forest Service officials, is beginning to fill a human-made pond, threatening to eliminate it as a drinking source for cattle and wildlife. Moreover, the entire mountainside is in danger of collapse, according to a Forest Service official.”
In a statement shared by Politico, Representative Raúl Grijalva, who requested the report, said, “This racist political stunt has been an ineffective waste of billions of American taxpayers’ dollars—and now we know it has caused immeasurable, irreparable harm to our environment and cultural heritage as well.”
In related news, Republicans have added funding to expand Trump’s wall to their list of spending demands, with some GOP reps suggesting they would shut down the government if they don’t get it.
US border wall construction damaged Native burial site: Government report
New report has found that efforts to expedite construction came at expense of sensitive ecosystems, Indigenous sites.
A section of border wall in the US state of Arizona [Al Jazeera via Center for Biological Diversity]
Barrier construction along the United States’ southern border has damaged sensitive ecosystems, public lands and Indigenous cultural sites, a report by a nonpartisan government research agency has found.
Released to the public on Thursday, the 72-page report marks the first independent effort from the Government Accountability Office (GAO) to assess the destruction caused by building the border wall.
It describes government contractors “blasting” a sacred Indigenous burial with explosives and leaving a mountainside “in danger of collapse”, among other incidents of harm.
The report focuses on a period from 2017 through January 2021, during the administration of former President Donald Trump. While the document never mentions Trump by name, it explains that federal authorities at the time relied on national security provisions to bypass existing protections.
“Federal agencies built about 450 miles [724 kilometres] of barriers along the US southwest border. To expedite construction, they waived federal environmental and other laws,” the GAO said in its summary.
“The construction harmed some cultural and natural resources, for example, by blasting at a tribal burial site and altering water flows.”
The report is the most comprehensive study yet of the border wall’s adverse impacts. It comes as immigration remains a flashpoint in US politics, particularly with the 2024 presidential election on the horizon.
“This report lays bare the damage the wall has inflicted on wildlife, public lands, and Indigenous cultural sites,” Laiken Jordahl, a southwest conservation advocate with the Center for Biological Diversity, told Al Jazeera.
“This report by a nonpartisan, fact-based agency confirms what we have been raising alarm over for years.”
Trump made the promise of an imposing wall on the US-Mexico border a centrepiece of his 2016 presidential campaign, which frequently leaned into anti-immigrant rhetoric and portrayed migrants as sources of crime and violence.
Chants of “Build the wall” became a staple of Trump’s campaign rallies.
Those cries are part of a growing international trend. Over the last two decades, the number of border barriers has been on the rise, with countries like the Dominican Republic, Poland and India taking steps to erect or complete fences and walls.
The Migration Policy Institute estimates that, as of 2022, 74 border barriers existed across the globe, compared with less than a dozen at the end of the Cold War.
However, the GAO report suggests steep consequences for environmental and cultural resources if construction is not evaluated beforehand.
“Before building, the Department of Homeland Security [DHS] assessed some potential effects of the construction,” the report’s website said. “But federal officials and stakeholders said they didn’t get enough information from DHS to give meaningful input.”
Construction efforts were complicated by the geography of the US’s southern border: Many sections run through rugged and inhospitable territory, including deserts, mountains and even coastal beaches.
Inhospitable terrain can complicate construction efforts along the US-Mexico border [Al Jazeera via Center for Biological Diversity]
To expedite construction through these landscapes, the Trump administration relied on the 2005 Real ID Act, which allows the government to waive laws and regulations that might pose an impediment to border walls and roads.
While previous administrations had invoked the Real ID Act, the Trump administration did so with unprecedented zeal, utilising it between 25 and 30 times, compare with just five during the Bush administration.
The Trump administration also declared undocumented crossings at the southern border a national emergency, empowering the government to overrule existing laws in the name of national security.
“The Trump administration cast those laws aside and ploughed forward with no thought about the consequences,” Jordahl said.
That authority allowed the government to overrule concerns from Indigenous communities in areas where the government wanted to move forward with construction, such as an oasis with sacred value to the Tohono O’odham Nation in Arizona known as Quitobaquito Springs.
“Since O’odham ancestors inhabited the area for thousands of years, it is home to several O’odham burial sites,” the report reads.
“According to Tohono O’odham Nation officials, contractors cleared a large area near the springs, destroying a burial site that the tribe had sought to protect.”
Ultimately, Trump completed 737km (458 miles) of border construction, though much of it overlapped with existing barriers. The GAO found 81 percent of the Trump wall replaced barriers erected under predecessors like former President George W Bush, rather than breaking new ground.
During his presidential campaign, current President Joe Biden promised to put an end to border wall construction, saying that “not another foot” would be built during his time in office.
A saguaro cactus lies destroyed near a border construction site in the state of Arizona [Al Jazeera via Center for Biological Diversity]
Biden halted construction upon taking office in January 2021. However, the GAO report offered a warning about suspending all resources to the border wall area: “Pausing construction and cancelling contracts also paused restoration work — such as completing water drainage structures and reseeding disturbed areas with native vegetation.”
Jordahl, meanwhile, believes that reversing the damage will require going even further.
“Ultimately, we want to see this wall removed from sensitive ecosystems where there has been damage to wildlife,” he said.
SOURCE: AL JAZEERA
How scientists are trying to save Canada’s canola crops
1 day ago Duration7:37
Persistent drought is killing canola crops in southern Alberta, but a scientist at the University of Calgary thinks he’s found a solution. CBC’s Nick Purdon goes to the prairies to learn more about the gene-editing breakthrough and what it could mean for the future of farming.
The spatial distribution and abundance of AVIRIS-NG CH4 hotspots (enlarged as points for visibility) around example beaver ponds, compared to non-beaver waterbodies. (a) Stream network and analysis buffer (10–60 m) with extensive beaver pond complex of multiple dams and ponds, (b) headwater stream with small beaver pond in stream, and (c) examples of beaver and non-beaver lakes. Imagery is from NASA AVIRIS-NG, acquired on 2018-07-24 . Credit: Environmental Research Letters (2023). DOI: 10.1088/1748-9326/acde8e
The climate-driven advance of beavers into the Arctic tundra is likely causing the release of more methane—a greenhouse gas—into the atmosphere.
Beavers, as everyone knows, like to make dams. Those dams cause flooding, which inundates vegetation and turns Arctic streams and creeks into a series of ponds. Those beaver ponds and surrounding inundated vegetation can be devoid of oxygen and rich with organic sediment, which releases methane as the material decays.
Methane is also released when organics-rich permafrost thaws as the result of heat carried by the spreading water.
A study linking Arctic beavers to an increase in the release of methane was published in July in Environmental Research Letters.
The lead author is Jason Clark, a former postdoctoral fellow at the University of Alaska Fairbanks Geophysical Institute. Research Professor Ken Tape, also of the Geophysical Institute, was Clark's adviser and is a co-author. Other co-authors include Benjamin Jones, a research assistant professor at the UAF Institute of Northern Engineering; and researchers from the National Park Service and NASA's Jet Propulsion Laboratory.
Tape has done extensive research about the northward migration of beavers and their resultant impact on the Arctic environment.
"What we found is that there are lots of methane hotspots right next to ponds and they start to diminish as you go away from the pond," he said.
The new study is the first to link large numbers of new beaver ponds to methane emissions at the landscape scale. It suggests that beaver engineering in the Arctic will at least initially increase methane release.
"We say 'initially' because that's the data we have," Tape said. "What the longer-term implications are, we don't know."
As a greenhouse gas, methane is 25 times more potent than carbon dioxide at trapping heat in Earth's atmosphere.
It accounts for about 20 percent of global greenhouse gas emissions, according to the U.S. Environmental Protection Agency. The agency says human activities have more than doubled atmospheric methane concentrations in the past two centuries.
The new research focused on 166 square miles of the lower Noatak River basin in Northwest Alaska. Data was obtained by airborne hyperspectral imaging through NASA's Arctic-Boreal Vulnerability Experiment program.
Hyperspectral cameras image an area in hundreds of wavelengths across the electromagnetic spectrum, including many not visible to the human eye. That differs from other cameras, which typically only image in the primary colors of red, green and blue.
The researchers compared the location of methane hot spots to the locations of 118 beaver ponds and to a number of nearby unaffected stream reaches and lakes. They analyzed the area up to approximately 200 feet from the perimeter of each water body and found a "significantly greater" number of methane hot spots around beaver ponds.
"We have these datasets that largely overlap, in space and mostly in time," Tape said. "It's kind of a simple design relying on a new tool."
Additional research about the relationship between beaver migration and Arctic methane release will occur next year.
More information: Jason A Clark et al, Do beaver ponds increase methane emissions along Arctic tundra streams?, Environmental Research Letters (2023). DOI: 10.1088/1748-9326/acde8e
Canadian Natural expects Trans Mountain expansion project to be delayed -letter
September 07, 2023
(Reuters) - Canadian Natural Resources Ltd, a major shipper on the Trans Mountain oil pipeline expansion (TMX), expects the project will be delayed until at least the second quarter of 2024, the company said in a letter to Canadian regulators on Thursday.
Trans Mountain Corp (TMC), the Canadian government-owned corporation building the long-delayed project, has said the expanded pipeline will start shipping oil late in the first quarter of next year.
Canadian Natural said it expected the pipeline's start date to be delayed because TMC is asking regulators for a route deviation on a 1.3-km (0.8 mile) section just south of Kamloops, British Columbia.
"Although Canadian Natural hopes for an earlier Commencement Date, unfortunately, it is probable that the Commencement Date will be delayed into Q2 or later in 2024," the letter to the Canada Energy Regulator (CER) said.
TMC did not immediately respond to a request for comment.
TMX will treble the flow of oil sands crude from Alberta to Canada's Pacific Coast to 890,000 barrels per day, but the expansion has been dogged by years of regulatory delays and environmental opposition.
It was bought by the Canadian government in 2018 to ensure it got built, but has seen costs quadruple to C$30.9 billion. TMC is currently locked in a dispute with oil shippers over higher-than-expected tolls.
Canadian Natural's submission to the CER was one of a number of letters from TMX shippers, including Cenovus Energy and Suncor Energy, filed on Thursday.
The companies argued TMX's proposed interim tolls are excessive and called for a review of why the cost of the pipeline escalated so much during construction.
(Reporting by Nia Williams; editing by Jonathan Oatis)
By Nia Williams
Three Ex-Canadian Fighter Pilots Are Training Chinese Pilots in China
A PLA Hongdu JL-10, supersonic advanced jet trainer, performs during the Zhuhai Airshow in Zhuhai in ... [+]
FUTURE PUBLISHING VIA GETTY IMAGES
Last Fall’s news of British and American former military fighter pilots training Chinese pilots in China just got a refresh with a new Canadian probe into ex-RCAF pilots training the Chinese.
Canada’s The Globe And Mail newspaper reported that the Royal Canadian Mounted Police (RCMP) are investigating three former Royal Canadian Air Force (RCAF) fighter pilots who are training military and civilian pilots in China under the auspices of the Test Flying Academy of South Africa (TFASA).
The RCMP’s probe joins UK and American investigations of ex-military fighter pilots from their respective countries training Chinese military pilots in NATO and western tactics and fighter operations which arose last year.
According to The Globe, Canadian security officials attempted to contact the former RCAF pilots in late August. Canada’s Department of National Defence says it referred the matter to the RCMP which is looking at three individuals - Paul Umrysh, Craig Sharp and David Monk in connection with training Chinese pilots in China.
The flight school they work for, TFASA is headquartered at Oudtshoorn Airfield in Western Cape region of South Africa. Aviation Week & Space Technologyreported that it was formed in 2003.
Its chairman is Jean Rossouw, a former test pilot with the South African Air Force (SAAF) and a director of the China-linked Avic-International Flight Training Academy. TFASA CEO, C. Jurie van Wyngaard, is also a SAAF pilot who previously held roles at Pilatus and Saab
TFASA has already been the subject of U.S. and UK scrutiny. In June, the U.S. government imposed export controls on TFASA and other firms it asserts are “providing training to Chinese military pilots using Western and NATO sources.”
The company reacted to the export controls in a statement explaining that they do not “affect TFASA’s day to day operations”. The statement asserted that it has operated “with the full knowledge of NATO defence and security agencies for over a decade”.
TFASA added that “over the past ten years almost 70% of Chinese pilot cadets who received training internationally do so in the United States; all Chinese pilot cadets trained by TFASA are drawn from, and return to, exactly the same talent pool as those trained in the United States.”
That may or may not be true but the training that TFASA references is commercial air transport pilot training, not the Operational Pilot & Specialist training it lists among its business sectors.
The Globe attempted to contact the Canadian pilots but instead got a response from TFASA’s spokesman who maintained that the flight training they are conducting only involves unclassified procedures and that training materials are derived either from open sources or from the clients themselves. “The training TFASA provides never includes information about NATO,” the spokesman affirmed.
What appears to be Western aircrew in front of a Chinese FTC-2000 jet trainer in an image from the ... [+]
TFASA
Is that credible? I spoke to a highly-placed background source in the contract adversary services (ADAIR) industry who opined that at a glance, TFASA’s expertise would appear to be more in the developmental test space but also noted that its Operational Pilot & Specialist training focus would simply not allow it to steer away from NATO tactics and procedures.
“If you’re teaching someone to develop a tactic, who are the bad guys? It’s not really pure for them to say, ‘We don’t ever mention NATO or talk about NATO tactics’. There always has to a Blue Air [i.e. China] and a Red Air [NATO/U.S.].”
The source emphasized that TFASA has “no play” in the legitimate Western ADAIR industry and is not even a recognized name. The mere exercise of placing a Chinese student pilot in one cockpit with a Canadian fighter pilot trained in NATO doctrine would inevitably produce Western training and tactical insights for the student the source agrees.
Open-source information of fighter tactics is widely available, even in the flight-simulation video games popular with two generations of gamers, simulations which can offer a baseline illustration of Western fighter tactics.
However, they have limits. Games won’t generally tell a player how to defeat a specific real-world missile but tactical fast-jet students would very much want to know the answer. Are they asking their TFASA instructors? What answers might they get?
Despite the apparent conflict with Western values illustrated by the RCAF pilots’ work with TFASA, their employment and the school’s contracts with Chinese students is not strictly illegal. TFASA stresses that it operates in compliance with South African law, as well as the laws of any other country it operates in, and that it has “systems” in place to ensure that Western-trained instructors don’t divulge classified information.
According to local South African media outlet news24, TFASA was specifically created with China in mind. It used South Africa's ties to China as well as its relationship with Western powers to position itself as an intermediary, scooping Chinese business with its ability to hire Western ex-military pilots as instructors.
But what kind of instructors are they? Would they be qualified and welcome to work with Western ADAIR firms? My source was adamant that only pilots with previous specific military adversary/aggressor experience (mostly U.S. military) are hired at most U.S. firms. At one in particular, pilot positions are filled by word of mouth, the firm does not advertise.
American firms now vet candidates for possible exposure to China-linked operations or Chinese instruction backgrounds. “I don’t think you’re going to find a connection between ADAIR in the U.S. and the kind of things that [you see] in this example,” the source asserts.
That contrasts with TFASA which an Australian pilot told Reuters actively targets Australian, British, Canadian, New Zealander and American pilots with pay packages worth more than £200,000 ($226,000) a year.
Another image formerly on TFASA's website appears to show Western pilots stepping from a Guizhou ... [+]
TEST FLYING ACADEMY OF SOUTH AFRICA
A final note worth passing on is that the Western pilots who have opted to work training Chinese pilots for firms like TFASA are not considered high level tactics experts by the commercial ADAIR industry.
“We know people who have gone elsewhere,” my source says. “We know people who go to the Middle East, to UAEUAE+0.4% for example. They’re not the people we work with.”
Highly trained aggressors or not, they can still offer useful insights to the Chinese, even if they strive to draw the line somewhere. The Globe asked one of the RCAF pilots under scrutiny to address speculation that the Canadians are training students on Chinese warplanes such as the Chengdu J-10 or J-11B multi-role fighters.
The pilot did not respond, and TFASA did not offer any comment.
How did plants first evolve into all different shapes and sizes? We mapped a billion years of plant history to find out
by Philip C J Donoghue, James Clark and Sandy Hetherington, The Conversation
From minuscule moss to colourful flowers and tall trees. Credit: Philip Donoghue / James Clark
Plants range from simple seaweeds and single-celled pond scum, through to mosses, ferns and huge trees. Paleontologists like us have long debated exactly how this diverse range of shapes and sizes emerged, and whether plants emerged from algae into multicellular and three-dimensional forms in a gradual flowering or one big bang.
To answer this question, scientists turned to the fossil record. From those best-preserved examples, like trilobites, ammonites and sea urchins, they have invariably concluded that a group's range of biological designs is achieved during the earliest periods in its evolutionary history.
In turn, this has led to hypotheses that evolutionary lineages have a higher capacity for innovation early on and, after this first phase of exuberance, they stick with what they know. This even applies to us: all the different placental mammals evolved from a common ancestor surprisingly quickly. Is the same true of the plant kingdom?
In our new study, we sought to answer this question by looking for certain traits in each major plant group. These traits ranged from the fundamental characteristics of plants—the presence of roots, leaves or flowers—to fine details that describe the variation and ornamentation of each pollen grain. In total, we collected data on 548 traits from more than 400 living and fossil plants, amounting to more than 130,000 individual observations.
We then analyzed all this data, grouping plants based on their overall similarities and differences, all plotted within what can be thought of as a "design space." Since we know the evolutionary relationships between the species, we can also predict the traits of their extinct shared ancestors and include these hypothetical ancestors within the design space, too.
For example, we will never find fossils of the ancestral flowering plant, but we know from its closest living descendants that it was bisexual, radially symmetric, with more than five spirally arranged carpels (the ovule-bearing female reproductive part of a flower). Together, data points from living species, fossils and predicted ancestors reveal how plant life has navigated design space through evolutionary history and over geological time.
We expected flowering plants to dominate the design space since they make up more than 80% of plant species, but they don't. In fact, the living bryophytes—mosses, liverworts and hornworts—achieve almost as much variety in their body forms.
This may not be entirely surprising since the three lineages of bryophytes have been doing their own thing for more than three times as long as flowering plants. And despite their diminutive nature, even the humble mosses are extraordinarily complex and diverse when viewed through a microscope.
The evolutionary relationships conveyed by the branching genealogy in the above plot show that there is, generally, a structure to the occupation of design space—as new groups have emerged, they have expanded into new regions. However, there is some evidence for convergence, too, with some groups like the living gymnosperms (conifers and allies) and flowering plants plotting closer together than they do to their common ancestor.
The two axes summarize the variation in anatomical design among plants. Colored dots represent living groups while the black dots represent extinct groups known only from fossils. The lines connecting these groupings represent the evolutionary relationships among living and fossil groups, plus their ancestors, inferred from evolutionary modelling. (The chlorophytes and charophytes are marine and freshwater plants while the remaining groups are land plants. Angiosperms are flowering plants). Credit: Philip Donoghue et al / Nature Plants
Nevertheless, some of the distinctiveness of the different groupings in design space is clearly the result of extinction. This is clear if we consider the distribution of the fossil species (black dots) that often occur between the clusters of living species (colored dots).
So how did plant body plan diversity evolve?
Overall, the broad pattern is one of progressive exploration of new designs as a result of innovations that are usually associated with reproduction, like the embryo, spore, seed and flower. These represent the evolutionary solutions to the environmental challenges faced by plants in their progressive occupation of increasingly dry and challenging niches on the land surface. For example, the innovation of seeds allowed the plants that bear them to reproduce even in the absence of water.
Over geological time, these expansions occur as episodic pulses, associated with the emergence of these reproductive innovations. The drivers of plant anatomical evolution appear to be a combination of genomic potential and environmental opportunity.
Plant disparity suggests that the big bang is a bust
None of this fits with the expectation that evolutionary lineages start out innovative before becoming exhausted. Instead, it seems fundamental forms of plants have emerged hierarchically through evolutionary history, elaborating on the anatomical chassis inherited from their ancestors. They have not lost their capacity for innovation over the billion or more years of their evolutionary longevity.
So does that make plants different from animals, studies of which are the basis for the expectation of early evolutionary innovation and exhaustion? Not at all. Comparable studies that we have done on animals and fungi show that, when you study these multicellular kingdoms in their entirety, they all exhibit a pattern of episodically increasing anatomically variety. Individual lineages may soon exhaust themselves but, overall, the kingdoms keep on innovating.
This suggests a general pattern for evolutionary innovation in multicellular kingdoms and also that animals, fungi and plants still have plenty of evolutionary juice in their tanks. Let's hope we're still around to see what innovation arises next.
More information: James W. Clark et al, Evolution of phenotypic disparity in the plant kingdom, Nature Plants (2023). DOI: 10.1038/s41477-023-01513-x
