Thousands of marine animals are tagged for a variety of research and conservation purposes, but at present the information gathered isn’t widely used to track climate change and other shifts in the oceans.

Instead, monitoring is mostly done by research vessels, underwater drones and thousands of floating sensors that drift with the currents. However, large areas of the ocean still remain under-sampled — leaving gaps in our knowledge.

A team led by the University of Exeter says animals carrying sensors can fill many of these gaps through natural behaviour such as diving under ice, swimming in shallow water or moving against currents.

“We want to highlight the massive potential of animal-borne sensors to teach us about the oceans,” said lead author Dr David March, of Centre for Ecology and Conservation on Exeter’s Penryn Campus in Cornwall.

“This is already happening on a limited scale, but there’s scope for much more.

“We looked at 183 species — including tuna, sharks, rays, whales and flying seabirds — and the areas they are known to inhabit.

“We have processed more than 1.5 million measurements from floating sensors to identify poorly sampled areas (18.6% of the global ocean surface).”

“By comparing this with gaps in current observations by drifting profiling sensors (known as Argo floats) we identified poorly sampled areas where data from animal sensors would help fill gaps,” said Professor Brendan Godley, who leads Exeter Marine.

“These include seas near the poles (above 60º latitude) and shallow and coastal areas where Argo profilers are at risk of hitting the land.

“The Caribbean and seas around Indonesia, as well as other semi-enclosed seas, are good examples of places where Argo profilers struggle because of these problems.”

Tagged seals in the poles have already complemented ocean observing systems because they can reach areas under ice that are inaccessible to other instruments.

The study suggests data collected by turtles or sharks could also enhance ocean monitoring in other remote and critical areas such as tropical regions, with large influence on global climate variability and weather.

The researchers say their work is a call for further collaboration between ecologists and oceanographers.

Professor Godley added: “It is important to note that animal welfare is paramount and we are only suggesting that animals that are already being tracked for ethically defensible and conservation-relevant ecological research be recruited as oceanographers. We do not advocate for animals being tracked solely for oceanography.”

The research team included the Balearic Islands Coastal Observing and Forecasting System (SOCIB), the University of St Andrews, the Mediterranean Institute of Advanced Studies and the Spanish Institute of Oceanography.

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An incorrect posture leads to injuries

“Doing workouts incorrectly can definitely lead to injuries. Technique is really important, especially if you start adding weights into your workout as they increase the load on the joints and the work required from the muscles,” says De Lacy. When patients present her with gym-related injuries, De Lacy first finds out when and how they occurred. “Timing of the injury is important for me to know, whether it is an acute or chronic injury as the management thereof is different,” she says.

The injury occurred is necessary to note as well, so that she can help to prevent her patients from injuring themselves again in the future. “There isn’t one recipe to follow when trying to continue training whilst injured, there are many factors to consider, namely: the nature and degree of the injury, the caused of the injury, what you’re training for (if it’s an event), the time between injury and event date will determine your management,” says De Lacy.

The solution…

Margeaux says, she advocates “active rest”, which means resting from the aggravating activity. “If you’ve got runners knee from running, one way of doing an active rest exercise is by swimming to keep fit. Every case is different and you should contact your healthcare provider before continuing to exercise through injury,” she says.

^{This article was originally published on www.womenshealthsa.co.za}

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Review of old ideas, analysis of old collections

To conduct their study, the researchers recorded the diameters of 1,200 ostrich eggshell beads unearthed from 30 sites in Africa dating to the last 10,000 years. Many of these bead measurements were taken from decades-old unstudied collections, and so are being reported here for the first time. This new data increases the published bead diameter measurements from less than 100 to over 1,000, and reveals new trends that oppose longstanding beliefs.

The ostrich eggshell beads reflect different responses to the introduction of herding between eastern and southern Africa. In southern Africa, new bead styles appear alongside signs of herding, but do not replace the existing forager bead traditions. On the other hand, beads from the eastern Africa sites showed no change in style with the introduction of herding. Although eastern African bead sizes are consistently larger than those from southern Africa, the larger southern African herder beads fall within the eastern African forager size range, hinting at contact between these regions as herding spread. “These beads are symbols that were made by hunter-gatherers from both regions for more than 40,000 years,” says lead author Jennifer Miller, “so changes — or lack thereof — in these symbols tells us how these communities responded to cultural contact and economic change.”

Ostrich eggshell beads tell the story of ancient interaction

The story told by ostrich eggshell beads is more nuanced than previously believed. Contact with outside groups of herders likely introduced new bead styles along with domesticated animals, but the archaeological record suggests the incoming influence did not overwhelm existing local traditions. The existing customs were not replaced with new ones; rather they continued and incorporated some of the new elements.

In eastern Africa, studied here for the first time, there was no apparent change in bead style with the arrival of herding groups from the north. This may be because local foragers adopted herding while retaining their bead-making traditions, because migrant herders possessed similar traditions prior to contact, and/or because incoming herders adopted local styles. “In the modern world, migration, cultural contact, and economic change often create tension,” says Sawchuk, “ancient peoples experienced these situations too, and the patterns in cultural objects like ostrich eggshell beads give us a chance to study how they navigated these experiences.”

The researchers hope that this work inspires a renewed interest into ostrich eggshell beads, and recommend that future studies present individual bead diameters rather than a single average of many. Future research should also investigate questions related to manufacture, chemical identification, and the effects of taphonomic processes and wear on bead diameter. “This study shows that examining old collections can generate important findings without new excavation,” says Miller, “and we hope that future studies will take advantage of the wealth of artifacts that have been excavated but not yet studied.”

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“In the past, people’s lifespans were much shorter, so some of these inflammatory and autoimmune diseases that can appear in the second half of life were not so relevant,” says first author Jorge Dominguez-Andres (@dominjor), a postdoctoral researcher at Radboud Institute for Molecular Life Science in the Netherlands. “Now that we live so much longer, we can see the consequences of infections that happened to our ancestors.”

One of the body’s best defenses against infectious diseases is inflammation. Dominguez-Andres and senior author Mihai Netea, a Radboud University immunologist and evolutionary biologist, compiled data from genetics, immunology, microbiology, and virology studies and identified how the DNA from people within different communities commonly infected with bacterial or viral diseases was altered, subsequently allowing for inflammation. While these changes made it more difficult for certain pathogens to infect these communities, they were also associated with the emergence — over time — of new inflammatory diseases such as Crohn’s disease, Lupus, and inflammatory bowel disease.

“There seems to be a balance. Humans evolve to build defenses against diseases, but we are not able to stop disease from happening, so the benefit we obtain on one hand also makes us more sensitive to new diseases on the other hand,” says Dominguez-Andres. “Today, we are suffering or benefiting from defenses built into our DNA by our ancestors’ immune systems fighting off infections or growing accustomed to new lifestyles.”

For example, the malaria parasite Plasmodium sp. has infected African populations for millions of years. Because of this, evolutionary processes have selected people with DNA that favors resistance to infections by causing more inflammation in the body. In doing so, this has also contributed to making modern Africans prone to developing cardiovascular diseases, such as atherosclerosis, later in life.

Dominguez-Andres and Netea also write about how the early-human ancestors of Eurasians lived in regions still inhabited by Neanderthals and interbred. Today, people with remainders of Neanderthal DNA can be more resistant against HIV-1 and ‘staph’ infections, but are also more likely to develop allergies, asthma, and hay fever.

The negative side effects of changes in each population’s immune systems are a relatively recent finding. “We know a few things about what is happening at the genetic level in our ancestry, but we need more powerful technology. So, next generation sequencing is bursting now and allowing us to study the interplay between DNA and host responses at much deeper levels,” says Dominguez-Andres. “So, we are obtaining a much more comprehensive point of view.”

These technologies are also revealing how our immune systems are evolving in real time because of modern lifestyle changes. African tribes that still engage in hunting have greater bacterial gut diversity than urbanized African-Americans that eat store-bought foods. Also, changes in hygiene patterns seen in the last two centuries have improved sanitation, drinking water, and garbage collection, and have led to reduced exposure to infectious pathogens relative to previous times. As humans move toward processed foods and stricter hygiene standards, their bodies adapt by developing what researchers call “diseases of civilization,” such as type 2 diabetes.

Moving forward, Dominguez-Andres and Netea will expand their research to communities that fall outside African and Eurasian populations. “So far, all of the studies we went through are focused on populations with European and African descent, but they must also be extended to indigenous and other populations to improve the representation of human genetic diversity,” says Dominguez-Andres. “Lifestyles and ecologic natures can really differ and influence immune responses. So, more work needs to be done.”

This work was supported by a Spinoza Grant of the Netherlands Organization for Scientific Research and an ERC Advanced grant.

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“Our main aim was to create a convenient scientific platform that could enhance CO₂ fixation, which can help address challenges related to sustainable production of food and fuels and global warming caused by CO₂ emissions,” says senior author Ron Milo, at systems biologist at the Weizmann Institute of Science. “Converting the carbon source of E. coli, the workhorse of biotechnology, from organic carbon into CO₂ is a major step towards establishing such a platform.”

The living world is divided into autotrophs that convert inorganic CO₂ into biomass and heterotrophs that consume organic compounds. Autotrophic organisms dominate the biomass on Earth and supply much of our food and fuels. A better understanding of the principles of autotrophic growth and methods to enhance it is critical for the path to sustainability.

A grand challenge in synthetic biology has been to generate synthetic autotrophy within a model heterotrophic organism. Despite widespread interest in renewable energy storage and more sustainable food production, past efforts to engineer industrially relevant heterotrophic model organisms to use CO₂ as the sole carbon source have failed. Previous attempts to establish autocatalytic CO₂ fixation cycles in model heterotrophs always required the addition of multi-carbon organic compounds to achieve stable growth.

“From a basic scientific perspective, we wanted to see if such a major transformation in the diet of bacteria — from dependence on sugar to the synthesis of all their biomass from CO₂ — is possible,” says first author Shmuel Gleizer (@GleizerShmuel), a Weizmann Institute of Science postdoctoral fellow. “Beyond testing the feasibility of such a transformation in the lab, we wanted to know how extreme an adaptation is needed in terms of the changes to the bacterial DNA blueprint.”

In the Cell study, the researchers used metabolic rewiring and lab evolution to convert E. coli into autotrophs. The engineered strain harvests energy from formate, which can be produced electrochemically from renewable sources. Because formate is an organic one-carbon compound that does not serve as a carbon source for E. coli growth, it does not support heterotrophic pathways. The researchers also engineered the strain to produce non-native enzymes for carbon fixation and reduction and for harvesting energy from formate. But these changes alone were not enough to support autotrophy because E. coli‘s metabolism is adapted to heterotrophic growth.

To overcome this challenge, the researchers turned to adaptive laboratory evolution as a metabolic optimization tool. They inactivated central enzymes involved in heterotrophic growth, rendering the bacteria more dependent on autotrophic pathways for growth. They also grew the cells in chemostats with a limited supply of the sugar xylose — a source of organic carbon — to inhibit heterotrophic pathways. The initial supply of xylose for approximately 300 days was necessary to support enough cell proliferation to kick start evolution. The chemostat also contained plenty of formate and a 10% CO₂ atmosphere.

In this environment, there is a large selective advantage for autotrophs that produce biomass from CO₂ as the sole carbon source compared with heterotrophs that depend on xylose as a carbon source for growth. Using isotopic labeling, the researchers confirmed that the evolved isolated bacteria were truly autotrophic, i.e., CO₂ and not xylose or any other organic compound supported cell growth.

“In order for the general approach of lab evolution to succeed, we had to find a way to couple the desired change in cell behavior to a fitness advantage,” Milo says. “That was tough and required a lot of thinking and smart design.”

By sequencing the genome and plasmids of the evolved autotrophic cells, the researchers discovered that as few as 11 mutations were acquired through the evolutionary process in the chemostat. One set of mutations affected genes encoding enzymes linked to the carbon fixation cycle. The second category consisted of mutations found in genes commonly observed to be mutated in previous adaptive laboratory evolution experiments, suggesting that they are not necessarily specific to autotrophic pathways. The third category consisted of mutations in genes with no known role.

“The study describes, for the first time, a successful transformation of a bacterium’s mode of growth. Teaching a gut bacterium to do tricks that plants are renowned for was a real long shot,” Gleizer says. “When we started the directed evolutionary process, we had no clue as to our chances of success, and there were no precedents in the literature to guide or suggest the feasibility of such an extreme transformation. In addition, seeing in the end the relatively small number of genetic changes required to make this transition was surprising.”

The authors say that one major study limitation is that the consumption of formate by bacteria releases more CO₂ than is consumed through carbon fixation. In addition, more research is needed before it’s possible to discuss the scalability of the approach for industrial use.

In future work, the researchers will aim to supply energy through renewable electricity to address the problem of CO₂ release, determine whether ambient atmospheric conditions could support autotrophy, and try to narrow down the most relevant mutations for autotrophic growth.

“This feat is a powerful proof of concept that opens up a new exciting prospect of using engineered bacteria to transform products we regard as waste into fuel, food or other compounds of interest,” Milo says. “It can also serve as a platform to better understand and improve the molecular machines that are the basis of food production for humanity and thus help in the future to increase yields in agriculture.”

This work was supported by the European Research Council, the Israel Science Foundation, the Beck-Canadian Center for Alternative Energy Research, Dana and Yossie Hollander, the Helmsley Charitable Foundation, the Larson Charitable Foundation, the Estate of David Arthur Barton, the Anthony Stalbow Charitable Trust, and Stella Gelerman, Canada. The authors declare a provisional patent related to the manuscript.

Paleoanthropologists agree that Neanderthals disappeared around 40,000 years ago — about the same time that anatomically modern humans began migrating into the Near East and Europe. However, the role modern humans played in Neanderthal extinction is disputed. In this study, the authors used population modelling to explore whether Neanderthal populations could have vanished without external factors such as competition from modern humans.

Using data from extant hunter-gatherer populations as parameters, the authors developed population models for simulated Neanderthal populations of various initial sizes (50, 100, 500, 1,000, or 5,000 individuals). They then simulated for their model populations the effects of inbreeding, Allee effects (where reduced population size negatively impacts individuals’ fitness), and annual random demographic fluctuations in births, deaths, and the sex ratio, to see if these factors could bring about an extinction event over a 10,000-year period.

The population models show that inbreeding alone was unlikely to have led to extinction (this only occurred in the smallest model population). However, reproduction-related Allee effects where 25 percent or fewer Neanderthal females gave birth within a given year (as is common in extant hunter-gatherers) could have caused extinction in populations of up to 1,000 individuals. In conjunction with demographic fluctuations, Allee effects plus inbreeding could have caused extinction across all population sizes modelled within the 10,000 years allotted.

The population models are limited by their parameters, which are based on modern human hunter-gatherers and exclude the impact of the Allee effect on survival rates. It’s also possible that modern humans could have impacted Neanderthal populations in ways which reinforced inbreeding and Allee effects, but are not reflected in the models.

However, by showing demographic issues alone could have led to Neanderthal extinction, the authors note these models may serve as a “null hypothesis” for future competing theories — including the impact of modern humans on Neanderthals.

The authors add: “Did Neanderthals disappear because of us? No, this study suggests. The species’ demise might have been due merely to a stroke of bad, demographic luck.”

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“We always wonder how birds can fly and in different ways,” says corresponding author Cheng-Ming Chuong of the University of Southern California, Los Angeles. “Some soar like eagles, while others require rapid flapping of wings like hummingbirds.” Some birds, including ostriches and penguins, don’t fly at all.

“Such differences in flight styles are largely due to the characteristics of their flight feathers,” Chuong adds. “We wanted to learn how flight feathers are made so we can understand nature better and learn principles of bioinspired architecture.”

In the new study, the researchers put together a multidisciplinary team to look at feathers in many different ways, from their biophysical properties to the underlying molecular biology that allows their formation from stem cells in the skin. They examined the feathers of flightless ostriches, short-distance flying chickens, soaring ducks and eagles, and high-frequency flying sparrows. They studied the extremes by including hummingbirds and penguins. To better understand how feathers have evolved and changed over evolutionary time, the team also looked to feathers that are nearly 100 million years old, found embedded and preserved in amber in Myanmar.

Based on their findings, the researchers explain that feathers’ modular structure allowed birds to adapt over evolutionary time, helping them to succeed in the many different environments in which birds live today. Their structure also allows for the specialization of feathers in different parts of an individual bird’s body.

The flight feather is made of two highly adaptable architectural modules: the central shaft, or rachis, and the peripheral vane. The rachis is a composite beam made of a porous medulla that keeps feathers light surrounded by a rigid cortex that adds strength. Their studies show that these two components of the rachis allow for highly flexible designs that enabled to fly or otherwise get around in different ways. The researchers also revealed the underlying molecular signals, including Bmp and Ski, that guide the development of those design features.

Attached to the rachis is the feather vane. The vane is the part of the feather made up of many soft barbs that zip together. The researchers report that the vane develops using principles akin to paper cutting. As such, a single epithelial sheet produces a series of diverse, branched designs with individual barbs, each bearing many tiny hooklets that hold the vane together into a plane using a Velcro-like mechanism. Their studies show that gradients in another signaling pathway (Wnt2b) play an important role in the formation of those barbs.

To look back in time, the researchers studied recently discovered amber fossils, allowing them to explore delicate, three-dimensional feather structures. Their studies show that ancient feathers had the same basic architecture but with more primitive characteristics. For instance, adjacent barbs formed the vane with overlapping barbules, without the Velcro-like, hooklet mechanism found in living birds.

“We’ve learned how a simple skin can be transformed into a feather, how a prototypic feather structure can be transformed into downy, contour, or flight feathers, and how a flight feather can be modulated to adapt to different flight modes required for different living environments,” Chuong says. “In every corner and at different morphological scales, we were amazed at how the elegant adaption of the prototype architecture can help different birds to adapt to different new environments.”

The researchers say that, in addition to helping to understand how birds have adapted over time, they hope these bioinspired architectural principles they’ve uncovered can be useful in future technology design. They note that composite materials of the future could contribute toward the construction of light but robust flying drones, durable and resilient wind turbines, or better medical implants and prosthetic devices.

Team co-leader and biophysicist Wen Tau Juan of the Integrative Stem Cell Center of China Medical University Hospital, Taiwan, has already begun to explore the application of feather-inspired architectural principles in bio-material design. The team also hopes to learn even more about the molecular signals that allow the formation of such complex feather structures from epidermal stem cells that all start out the same.

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