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)
Thursday, January 18, 2024
Research Partners Find Six Million Acres of Deep-Sea Coral off Florida
NOAA and a consortium of research partners have discovered and mapped a vast deep-sea coral reef off the east coast of the United States. It is the likeliest habitat of its kind ever found, according to the consortium's newly-published study.
The team used three different multibeam sonar surveys to map the extent of the reef system. NOAA contributed the largest share of the data. Together, these survey campaigns covered almost all of the Blake Plateau, a rise located about 90 nautical miles off Florida, Georgia and South Carolina.
The total area surveyed is about the size of Florida, and the reef covered about 6.4 million acres - an area about the size of Vermont. They used an automated classification system to identify coral mounds in the survey data and found 83,000 probable hits. These mounds are distributed over an area about 280 nautical miles long and 60 nautical miles wide. The surveys were backed up and validated using 23 submersible dives.
Scientists dubbed the densest area of coral "Million Mounds" for its dense accumulation of the stony coral desmophyllum pertusum. These corals form large mounds that provide an important habitat for fish, including shelter for rearing young hatchlings. Some of these fish are commercially important for East Coast fisheries.
“For years we thought much of the Blake Plateau was sparsely inhabited, soft sediment, but after more than 10 years of systematic mapping and exploration, we have revealed one of the largest deep-sea coral reef habitats found to date anywhere in the world,” said Kasey Cantwell, operations chief for NOAA Ocean Exploration.
In a statement, study lead author Derek Sowers, Ph.D. said that the result showed how interagency partnerships could help the quest to map the 50 percent of U.S. waters that have yet to be mapped in high resolution.
NOAA added that the results will help guide policy on sustainable use and management of ocean resources in this area.
Salvors Will Dismantle Trawler That Ran Aground Near Portland, Maine
The U.S. Coast Guard has approved a plan to dismantle a trawler that ran aground near Portland, Maine over the weekend, according to local media.
The trawler Tara Lynn II grounded in the early hours of Saturday morning near Trundy Point, a headland located about five nautical miles southeast of Portland. Conditions on scene were difficult, with winds blowing to 45 knots and waves of about six feet. The area was so shallow that first responders had difficulty reaching the boat by water, and had to use the local fire department's 10-foot inflatable boat to rescue the crewmembers. Despite the hazards, the four fishermen on the boat were ferried the short distance to shore, two at a time.
Courtesy Cape Elizabeth Fire/Rescue
"We got washed past the spot where we wanted to extricate the people off the boat two times," said local fireman Lt. Nate Perry, speaking to Spectrum News. The small-boat team had to maneuver around the trawler's rigging, which was dangling in the water, and hold the boat steady alongside in rough conditions.
The site is well above water at low tide, and the wreck of the Tara Lynn II sits far up towards the shoreline. Parker Poole, a local salvor and tug operator, told the AP that he plans to drive excavators out on the flat to demolish the boat in place.
Researchers make links between woolly mammoths and colonization of the Americas
uOttawa professor and team go back 14,000 years to show links between mammoths and early hunter-gatherer communities
“THE NEW TOOLS DEVELOPED IN THIS RESEARCH WILL HELP WITH EFFORTS TO CONSERVE BIODIVERSITY, PROVIDING AN ANALOGUE TO MODERN TIMES". CLÉMENT BATAILLE — ASSOCIATE PROFESSOR, DEPARTMENT OF EARTH AND ENVIRONMENTAL SCIENCES, FACULTY OF SCIENCE
Imagine journeying back in time to the era of woolly mammoths, some 14,000 years ago. That’s what a team of international researchers from the University of Ottawa, the University of Alaska Fairbanks, McMaster University and Adelphi University, and Indigenous scholars, managed to do. Using novel high-resolution isotope profiling (a sort of “paleo-GPS”), they were able to connect the dots between the wanderings of a woolly mammoth and the earliest known human settlements in the remote expanses of eastern Beringia (the land and maritime area between the Lena River in Russia and Canada’s Mackenzie River).
The paper, published in Science Advances, sheds light on the relationship between mammoths and early hunter-gatherer communities in the region. Through a detailed analysis of the mammoth’s remains and genetic connections, the researchers were able to reconstruct the life history and movements of this iconic species, providing evidence of overlapping mammoth/human habitats and of the possible role mammoths played in facilitating the peopling of the Americas.
This study focuses on a female woolly mammoth, “Élmayuujey’eh” (Elma), named by the Healy Lake (Alaska) Village Council, whose remains were discovered at Swan Point, the earliest archeological site in Alaska. Alongside the mammoth, the site also contained remains of a juvenile and a baby mammoth, indicating the presence of a herd in the area. This finding intrigued researchers and prompted further investigations into the movements and interactions between mammoths and early humans.
Clément Bataille (associate professor, Department of Earth and Environmental Sciences, Faculty of Science, University of Ottawa), lead author and PhD student Audrey Rowe (University of Alaska Fairbanks) and co-author Matthew Wooller (University of Alaska Fairbanks) conducted a detailed isotopic analysis of Élmayuujey’eh’s complete tusk. This allowed them to retrace the mammoth’s movements through her lifetime.
“Elma roamed extensively within the densest region of archaeological sites in Alaska,” says Rowe. “This suggests a close association between mammoths and early human hunting camps.”
Meanwhile, Hendrik Poinar and his team at McMaster University conducted genetic analyses of the remains of eight other individual mammoths found in the region. They determined that the Swan Point area likely served as a meeting ground for at least two closely related herds. This suggests that mammoths had social structures and exhibited herd behavior.
Solving the mystery of human-mammoth coexistence
“This research gives new insights into how humans and mammoths interacted when humans first came to the Americas,” says Bataille. “It seems that mammoths, which were plentiful in eastern Beringia and an important food source, attracted humans to the area.”
It’s not the first time that this geolocation technique has been used to retrace the mobility of a mammoth. The team created it for a study of a 17,000 year old male named Kik, who lived in a colder period when humans hadn’t yet arrived, unlike Elma.
Interestingly, Kik and Elma showed very different mobility behaviours. Kik moved freely over long distances across large valleys and tundra plains using regular core areas, whereas Elma, while still using similar core areas, moved shorter distances, maintaining a high elevation. This raises questions about the role of humans and climate change in influencing the mobility of this ancient species.
This high-resolution isotope profiling technique can be applied to uncover the ecology of many other extinct species. Used with genetic analysis, it’s an innovative way to learn about how ancient species responded to climate change and human pressures, and what ultimately caused their extinction.
By shedding light on mammoth ecology and lifeways and mammoths’ long-term interactions with climate change and humans, the study can help us predict how animals will respond to climate and human pressures in the future. “The new tools developed in this research, along with the insights into the ecology of extinct species, will help with efforts to conserve biodiversity, providing an analogue to modern times, where many large mammals are in danger of going extinct with human and climate perturbations,” says Bataille.
This study was funded in part by the NSERC Discovery Grants program and was published in Science Advances on January 17.
Hamilton, ON, Jan. 17, 2024 – An international team of researchers from McMaster University, University of Alaska Fairbanks and the University of Ottawa has tracked and documented the movements and genetic connections of a female woolly mammoth that roamed the earth more than 14,000 years ago.
She travelled hundreds of kilometres through northwestern Canada and Alaska over the course of her lifetime, which ended when she encountered some of the earliest people to have traveled across the Bering Land Bridge.
The last remaining woolly mammoths lived alongside the region’s first peoples for at least 1,000 years, but little is known about how the mammoths moved across a landscape increasingly populated by people and whether those movements made them more vulnerable to hunting.
The mammoth at the centre of this study, named Élmayuujey’eh by the Healy Lake Village Council, was discovered at Swan Point, the earliest archaeological site in Alaska, which also contained remains of a juvenile and a baby mammoth. Mammoth remains have also been found at three other archaeological sites within 10 km of Swan Point.
Researchers conducted a detailed isotopic analysis of a complete tusk and genetic analyses of remains of many other individual mammoths to piece together their subject’s movements and relationships to other mammoths at the same site and in the vicinity. They determined that the Swan Point area was likely a meeting ground for at least two closely related, but distinct matriarchal herds.
The findings are published today in the journal Science Advances.
“This is a fascinating story that shows the complexity of life and behaviour of mammoths, for which we have very little insight,” says evolutionary geneticist Hendrik Poinar, director of the McMaster Ancient DNA Centre who led the team that sequenced the mitochondrial genomes of eight woolly mammoths found at Swan Point and other nearby sites to determine if and how they were related.
Researchers from the University of Alaska Fairbanks performed isotopic analyses of the tusk. Mammoth tusks grew like tree trunks, with thin layers marking steady growth and isotopes from different elements—oxygen and strontium, for example—provided information about the subject’s movement.
The female mammoth was approximately 20 years old when she died, having spent much of her life in a relatively small area of the Yukon. Researchers report that as she grew older, she travelled over 1000 km in just three years, settling in interior Alaska and dying near a closely related baby and juvenile, for which she may have been the matriarchal lead.
Mammoths are presumed to behave much like modern elephants, with females and juveniles living in close-knit matriarchal herds and mature males traveling alone or in looser male groups, often with larger home ranges than the females.
Researchers say using multiple forms of analysis, as in this study, allows them to make inferences about the behaviour of extinct mammoths.
The McMaster team extracted and analyzed ancient DNA from the tusk of Élmayuujey’eh, which revealed the mammoth was closely related to the other mammoths from the same site and more distantly related to others from a nearby site called Holzman.
Early human populations, with a deep understanding of mammoths and the technology to hunt them, took advantage of mammoth habitats, using scavenged and hunted remains as raw materials for tools, the researchers report.
In addition to the direct impact of hunting on mammoth populations, human activity and settlements may have also indirectly affected mammoth populations by curtailing their movements and their access to preferred grazing areas.
“For early people in Alaska, those localities were important for observation and appreciation, and also a source of potential food,” says Poinar.
The collected data suggests that people structured their seasonal hunting camps based on where mammoths gathered and may have played an indirect role in their local extinction in Alaska, which was compounded by a rapidly changing climate and changing vegetation.
Such deprivations did not appear to have affected the subject mammoth, though.
“She was a young adult in the prime of life. Her isotopes showed she was not malnourished and that she died in the same season as the seasonal hunting camp at Swan Point where her tusk was found,” said senior author Matthew Wooller, who is director of the Alaska Stable Isotope Facility and a professor at UAF’s College of Fisheries and Ocean Sciences.
“This is more than looking at stone tools or remains and trying to speculate. This analysis of lifetime movements can really help with our understanding of how people and mammoths lived in these areas,” says Tyler Murchie, a recent postdoctoral researcher at McMaster who conducted the ancient DNA analysis with Sina Baleka. “We can continue to significantly expand our genetic understanding of the past, and to address more nuanced questions of how mammoths moved, how they were related to one another and how that all connects to ancient people.”
The research was funded in part by the National Sciences and Engineering Research Council of Canada (NSERC).
CREDIT: YIWEN WANG , LEI CHEN , KAIHANG ZHU , CHENXI GUO , YU PU , ZHENYAO SHEN
Globally, non-point source pollution is an important source of water quality deterioration in rivers and lakes. A ditch-pond system, consisting of ditches and ponds, is considered to be similar to free-surface wetlands, linking pollution sources to the receiving water bodies. The ditch-pond system includes vegetation, microorganisms and sediment, which can slow down the flow velocity and promote the precipitation of particulate matter carried by running water. At the same time, ditch and pond systems reduces nitrogen and phosphorus concentrations, and those of other nutrients entering the downstream water by means of plant absorption, sediment adsorption and microbial degradation, so as to reduce agricultural non-point source pollution. As an important farming area in southern China, the Three Gorges Reservoir area covers a wide area of hills and serious soil erosion, which further exacerbates the problem of agricultural non-point source pollution. In China, ponds are mainly distributed in the eastern and southern regions. However, most of the studies on ditches and ponds have been conducted in the lowland areas, and there are few studies with field observations in upland areas. What kind of function the ditch-pond system plays in the water environment in the mountain catchment is worth studying deeply.
Large water bodies, especially lakes and wetlands, have been given more attention as important geographical features of global terrestrial systems. Compared with large water bodies, small water bodies such as ponds are common, but receive limited attention and are often ignored. Prof. Lei Chen and his team used high-resolution remote sensing data to analyze changes in ditches and ponds within the catchment. The results showed that over the past 15 years the length of ditches in the catchment and the number of small ponds (< 500 m2) have increased by 32% and 75%, respectively. The concentration of pollutants in the ditch and pond system was much higher than that in the mainstream in the catchment, indicating that dense ditch-pond network not only increases the confluence time, but also is more conducive to the interception of pollutants. By comparing the pollutant concentrations at the inlet and outlet of different ditches and ponds, it was found that the change rate of nutrient concentration in ditch-pond is mostly between –20% and 20%, indicating ditches and ponds can be both sources and sinks for agricultural pollutants. Although ditches and ponds are sometimes a source of pollutants, they help regulate the hydrology and water quality of catchment. In addition, this study also compared the effects of different texture ditches on pollutant interception. It was found that the interception effect of concrete ditch on particulate phosphorus is better than that of soil ditch in dry season. Based on the research results, we think that retaining the sediment in the ditch in dry season and cleaning the sediment in time in rainy season can help the ditch-pond system to transform from source to sink effectively. Therefore, the function of balancing the drainage and interception functions of the ditch-pond system can maximize its ecological role in the catchment.
This study has been published on the Journal of Frontiers of Agricultural Science and Engineering in 2023, DOI: 10.15302/J-FASE-2023517.
Associate Professor Andrew Baker from QUT School of Biology and Environmental Science said antechinuses are carnivorous marsupials well-known for suicidal sex sessions where all males die after the 1 to 3 week breeding period.
“During the breeding season, male and females mate promiscuously in frenzied bouts lasting as long as 14 hours. Certain stress-induced death follows for all males as surging testosterone causes cortisol to flood uncontrolled through the body, reaching pathological levels,” Professor Baker said.
“The males drop dead, which provides an opportunity for cheap energy gain via cannibalism for still-living males and pregnant or lactating female antechinuses.
“While cannibalistic behaviour has been reported in some dasyurids (the family which includes antechinuses, quolls and Tasmanian devils), it is very rare to observe in the wild.”
The photos of a mainland dusky antechinus (Antechinus mimetes) eating a dead member of its own species were taken on a trek to Point Lookout in New England National Park, NSW in August 2023.
Professor Baker said both the eaten and the eater in the photos were identified as mainland dusky antechinuses based on a combination of body size, foreclaw length, small ears and eyes, fur colour and shagginess, along with the capture location.
“In places such as Point Lookout where two antechinus species (Antechinus mimetes and the brown antechinus, A. stuartii) are living in the same area, the two slightly separated breeding periods provide the opportunity to cannibalise both their own and the other species.
“Each species may benefit from eating dead males of the other.
“For the earlier-breeding antechinus species, it may mean that pregnant and lactating females can get high-energy food by cannibalising the males of the later-breeding species as they die off.
“For the later-breeding species, both sexes may take the opportunity to cannibalise dead males of the earlier-breeding species, to help stack on weight and condition before their own breeding period commences.
“In the present study, the sex of the animal eating the dead antechinus is uncertain but it is most likely a male. Although males are believed to eat less than females during breeding, both sexes are known to eat at that time.
“The antechinus seen feeding on its dead comrade appeared vigorous and large-bodied, but it had damage to its right eye and hair loss on its arms and shoulders, which is associated with stress-induced decline in males. He was perhaps destined soon to become somebody else’s meal.”
The mystery behind why Alaskan horses, cryptodiran turtles and island lizards shrunk over time may have been solved in a new study.
The new theoretical research proposes that animal size over time depends on two key ecological factors: the intensity of direct competition for resources between species, and the risk of extinction from the environment.
Using computer models simulating evolution, the study, published today (Thursday, 18 January) in communications biology, identifies why some species gradually get smaller, as indicated by fossil records.
Dr Shovonlal Roy, an ecosystem modeller from the University of Reading who led the research, said: "Just like how we try to adapt to hot or cold weather depending on where we live, our research shows animal size can get bigger or smaller over long periods depending on the habitat or environment.
"In places and times where there's lots of competition between different species for food and shelter, animal sizes often get smaller as the species spread out and adapt to the distribution of resources and competitors. For example, small horses that lived in Alaska during the Ice Age rapidly shrank due to changes in the climate and vegetation.
“Where direct competition is less, sizes tend to get bigger, even though being really big and few in number can make animals more vulnerable to dying out – such as what happened with the dinosaurs.
“Changes in ecological factors help explain why fossil records shows such confusing mixes of size evolution patterns, with some lineages shrinking over time and others growing."
Cope’s rule
The research team carried out their study by challenging the contradictions fossil evidence posed to “Cope’s rule.” Cope’s rule refers to the tendency for certain animal groups to evolve larger body sizes over thousands and millions of years. The rule is named after Edward Cope, a 19th-century palaeontologist who was credited to have first noticed this pattern in the fossil record. For example, early horse ancestors were small dog-sized animals that increased in size over evolutionary time, ultimately producing the modern horse.
However, fossil evidence shows remarkably conflicting trends, with increased size in some groups but decreased size in others.
Evolutionary pressure
Using computer models simulating evolution, the study identified three distinct patterns of body-size change emerging under different conditions:
Gradual size increase over time: This happens when competition between species is determined mostly by their relative body sizes rather than niche differences. For example, several genera of marine animal species (e.g. invertebrates) gradually increased in size over millions of years.
Size increase followed by extinctions: Here the largest animals recurrently go extinct, opening opportunities for other species to take their place and evolve even bigger bodies, continuing the cycle. Mass extinctions hit large-bodied apex predators hardest. Very large mammals and birds are particularly vulnerable to extinction – for example, dinosaurs and giant flying reptiles.
Gradual size decrease over time: The simulations also predicted the opposite of Cope’s rule: species shrinking over time. This happens when competition is high and there is a degree of overlap in habitat and resource use. As species evolve apart into distinct niches, they face evolutionary pressure to reduce in size. Decline in size was previously reported for vertebrates, bony fish, cryptodiran turtles, Alaskan Pleistocene horses, and island lizards
