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Fishy trick lures life back to coral reefs
Source: scientificamerican https://www.scientificamerican.com/podcasts [Rephrase 1, 02'35]
An ancient critter may shed light on when mammals’ middle ear evolved By Carolyn GramlingDECEMBER 6, 2019 AT 8:00 AM
[Time 2] Exceptionally preserved skulls of a mammal that lived alongside the dinosaurs may be offering scientists a glimpse into the evolution of the middle ear.
The separation of the three tiny middle ear bones — known popularly as the hammer, anvil and stirrup — from the jaw is a defining characteristic of mammals. The evolutionary shift of those tiny bones, which started out as joints in ancient reptilian jaws and ultimately split from the jaw completely, gave mammals greater sensitivity to sound, particularly at higher frequencies (SN: 3/20/07). But finding well-preserved skulls from ancient mammals that can help reveal the timing of this separation is a challenge.
Now, scientists have six specimens — four nearly complete skeletons and two fragmented specimens — of a newly described, shrew-sized critter dubbed Origolestes lii that lived about 123 million years ago. O. lii was part of the Jehol Biota, an ecosystem of ancient wetlands-dwellers that thrived between 133 million and 120 million years ago in what’s now northeastern China.
The skulls on the nearly complete skeletons were so well-preserved that they were able to be examined in 3-D, say paleontologist Fangyuan Mao of the Chinese Academy of Sciences in Beijing and colleagues. That analysis suggests that O. lii’s middle ear bones were fully separated from its jaw, the team reports online December 5 in Science.
“This paper describes a spectacular fossil,” says vertebrate paleontologist Zhe-Xi Luo of the University of Chicago, who was not involved in the new study. But he’s not convinced that O. lii represents an evolutionary leap forward in mammalian ear evolution. [257 words]
[Time 3] Luo notes that O. lii is closely related to the mammal genus Maotherium, which lived around the same time and in roughly the same location. In Science in July, Luo and colleagues reported that a new analysis of Maotherium revealed that its middle ear bones were still connected to its jawbones by a strip of cartilage (SN: 7/18/19).
That finding, Luo says, was expected. Maotherium is well-known as a transitional organism, in which the middle ear bones had begun to rotate away from the jaw but were still loosely connected by that cartilage. There are numerous branches and twigs on the mammal family tree, Luo says, and evolution occurred at a different pace on them. But, he says, it’s unlikely that O. lii would have had separated ear bones when Maotherium didn’t, given the pair’s close positioning on the tree.
Luo says he also doesn’t find the study’s evidence that the separation was complete in O. lii convincing. Three of the four skulls in the study were missing all or part of the middle ear, and the gap between the middle ear bones and jaw in the fourth skull may have been a break that occurred during fossilization, he adds.
However, the new study’s researchers reject this idea. “It’s common that different interpretations may exist for a discovery in paleontology,” says vertebrate paleontologist Jin Meng of the American Museum of Natural History in New York, a coauthor of the study.
But, Meng says, none of the ear bones or the cartilage in any of the skulls show fractured or broken edges. That, he says, suggests that these features were already separated in the animals before their demise. [277words]
Source: Science News https://www.sciencenews.org/article/ancient-critter-may-shed-light-when-mammals-middle-ear-evolved
Science publishers review ethics of research on Chinese minority group December 6,2019
Two science publishers are reviewing the ethics of research papers in which scientists backed by China’s government used DNA or facial-recognition technology to study minority groups in the country, such as the predominantly Muslim Uyghur population. Springer Nature (which publishes Nature) and Wiley want to check that the study participants gave informed consent, after researchers and journalists raised concerns that the papers were connected to China’s heavy surveillance operations in the northwestern province of Xinjiang. China has attracted widespread international condemnation — and US sanctions — for mass detentions and other human-rights violations in the province. The Chinese government says that it is conducting a re-education campaign in the region to quell what it calls a terrorist movement.
“We are very concerned about research which involves consent from vulnerable populations,” says a spokesperson from Springer Nature (Nature’s news team is editorially independent of its publisher). The publishers’ announcements, which The New York Times reported on 4 December, follow rising concerns about the publication of such work.
Scientists say there are scores of such research papers in the literature. Earlier this week, Yves Moreau, a computational biologist at the Catholic University of Leuven in Belgium, wrote an opinion article in Nature warning of the dangers that accompany the proliferation of DNA profiling and calling for all unethical work in biometric research to be retracted to avoid giving its authors academic credence.
Ethical ambiguity Springer Nature said that this week it would add notes of concern about consent to two papers1,2 that reported studies using DNA from hundreds of Uyghurs to predict height or facial shape. One of the papers, published in Human Genetics1, was highlighted in a separate New York Times article, also published earlier this week, that described worries that the participants hadn’t given informed consent.
Both papers state that volunteers gave consent, and that the studies were approved by an ethics committee from the Institute of Forensic Science which is affiliated with China’s police and security authority.
"We are ordinary forensic scientists who carry out forensic research following the scientific research ethics norms," said Caixia Li of the Institute of Forensic Science in Beijing, a co-author on both papers1,2, in an e-mail to Nature’s news team. He noted that the “study” was approved by his institute, and said that “all individuals provided written informed consent”. [384 words]
[Time 5] Moreau says that it’s hard to see how Uyghur peoples could give free, informed consent to DNA or facial-recognition work — given that so many people in that ethnic group have been sent to internment camps (which China calls education facilities). “It is my opinion that no population-genetics research on Chinese populations can be considered ethical, because the risk of abuse is so pervasive.”
Springer Nature has identified a number of other ‘papers of concern’ published by its journals, the spokesperson adds, which are being investigated. And it has updated its guidance to editors and authors about the need to gain explicit and informed consent in studies that involve clinical, biomedical or biometric data from people. “All instances of non-compliance with our policies will result in appropriate editorial action, which may include retraction,” the spokesperson said.
Moreau says: “Expression of concerns are a welcome first step, but this is only meaningful if it is the start of a large-scale ethical review of all forensic population-genetic research on Chinese populations and of all biometric research.”
Under investigation Wiley, meanwhile, said it was opening a formal investigation into a 2018 article that described analysing a database of photos of Uyghur, Tibetan and Korean groups using various facial-recognition algorithms3. In September, four researchers, including Moreau, who were led by the advocacy group Tech Inquiry in Toronto, Canada, had asked Wiley to retract the paper because of the potential for abuse of facial-recognition technology, and the “racial overtones of the authors’ language”. One of the paper’s co-authors is affiliated with Curtin University in Perth, Australia, which this month also requested that Wiley review the paper.
Jack Poulson, an applied mathematician and former Google employee who is the founder of Tech Inquiry, says Curtin deserves public credit for its response. “If it’s clear that there’s any chance that a paper might contribute to human-rights violations, I think it’s fair to call for a retraction,” he says.
“We conducted an initial review of the paper in question and found the journal did follow existing guidelines,” a spokesperson for Wiley said, but confirmed that the publisher was now re-evaluating the paper. [353 words]
[Time 6] In its September letter, Tech Inquiry noted that, according to guidelines laid down by the Committee on Publication Ethics, a London-based publisher-advisory body, papers can be rejected on ethical grounds even if they come with approvals from an ethics committee (as the Wiley paper did). The guidelines also say that journals should take special care when the research is conducted on “vulnerable groups”, which Springer Nature has emphasized in its latest editorial policies. Nature’s news team asked the paper’s authors for comment, but they have not replied.
Widespread concerns There are numerous examples of papers that report the use of biometric technology to study Uyghur and other minority ethnic groups in China. Moreau wrote in his opinion article that he had identified 40 articles co-authored by members of the Chinese police in 3 leading forensic-genetics journals — published by Springer Nature and by Elsevier — that describe the DNA profiling of Tibetans and Muslim minorities. And of a wider sample of more than 500 forensic population-genetics studies in Chinese populations, he wrote, half had co-authors from China’s police force, military or judiciary.
A spokesperson for Elsevier said that the company is in the process of producing more comprehensive guidelines for the publication of genetic data, but that it was “unable to control the potential misuse of population data articles” by third parties after publication. Springer Nature also said that it would tighten its oversight of the academic-conference proceedings that it publishes. It said it would require that conference organizers — who have editorial oversight of what is presented — make sure that published proceedings comply with the publisher’s policies, and that it would reserve the right to retract proceedings that didn’t meet these requisites.
Journalists have previously raised concerns about numerous conference papers that describe studying Uyghur groups, including manuscripts from a biometrics conference held in Xinjiang in 2018 that Springer Nature published as a book4.
The Institute of Electrical and Electronics Engineers (IEEE) has also published conference proceedings describing facial-recognition analyses of Uyghur populations (see, for example, refs 5,6). Asked by Nature’s news team whether the IEEE, too, was reviewing the issues, the IEEE’s president and chief executive José Moura wrote: “IEEE recognizes the importance of protecting individuals who are involved in human subject research and the role of the Institutional Review Boards in that effort. IEEE is committed to reviewing our policies to ensure more consistent application of this process across the full range of IEEE publications.” [405words]
Source: Nature https://www.nature.com/articles/d41586-019-03775-y
Part III: Obstacle
Police Killings of Unarmed Black Americans May Affect Health of Black Infants
[Paraphrase 7] Michael Brown, Eric Garner, Tamir Rice—these are just a few of the unarmed African Americans killed by police officers in the past few years. Such incidents not only cause incalculable suffering in affected families but also have long-term impacts on communities’ overall well-being. Now a new study finds that such events are associated with negative health outcomes among unborn black infants.
Sociologist Joscha Legewie of Harvard University analyzed the birth records of nearly four million babies born in California in recent years and found that black infants born near police killings of unarmed black individuals were more likely to be born prematurely and have a lower birth weight. He did not find a similar correlation among white or Hispanic infants or black infants exposed to killings of armed black people or of those of other races. Maternal stress related to killings perceived as unjust or discriminatory may be contributing to the observed health impacts on black infants, Legewie says. Studies suggest preterm birth and low birth weight can negatively affect cognitive development, linking them with lower test scores and greater rates of attention deficit hyperactivity disorder. The findings were published Wednesday in Science Advances.
Police kill about 1,000 people in the U.S. every year, and a disproportionate number of them are minorities. Black individuals are killed at nearly three times the rate of white ones. Officers’ use of deadly force is often controversial, but when the person killed is unarmed, the impacts on communities can be especially devastating, prompting surges of collective grief, anger and fear.
Legewie hypothesized that the stress experienced by pregnant black women living in close proximity to police killings of unarmed black individuals could be contributing to poor birth outcomes. To investigate that potential effect, he examined data on all births in California between 2007 and 2016, including information about race and ethnicity, birth weight, gestational age, home location and other factors.
Then he combined this information with data on police killings in California between 2005 and 2017, which included the date and location of the events, the races of the people killed, and whether or not they were armed. Legewie analyzed the impact of proximity to a police killing (in kilometers)—at time intervals before and after the event, as well as during all three trimesters of pregnancy—on birth weight and gestational age (a measure of premature birth). He examined killings of black, white and Hispanic people, as well as the health of infants of corresponding races.
Based on his results, Legewie concludes that only killings of unarmed black individuals were significantly associated with the health of black infants. Although the exact mechanism is not known, he speculates that maternal stress from the killings may trigger cells in the placenta and fetal membranes to produce corticotropin-releasing hormone—which is known to cause premature birth and low birth weight.
To exclude other factors that could explain a link between police killings and poor birth outcomes, Legewie conducted several analyses. First, he used something called a “difference in difference” approach, comparing black infants born in areas exposed to the killings (before and after the events) with infants in demographically similar areas that had no reported killings. He then used another method to compare the health of siblings who were or were not exposed to a police killing while in the womb to reduce possible factors related to the mother.
Finally, he compared the correlation of police killings of people in different racial and ethnic groups to the health of infants of those groups to show that the situation was specific to black infants exposed to killings of unarmed black individuals.
The analysis is “interesting, relevant, very careful, very well executed,” says Florencia Torche, a professor of sociology at Stanford University, who was not involved in the study. “This finding aligns with prior scholarship suggesting that police violence—and in particular, police killings—have detrimental effects on black populations.” And it extends those effects to “the most innocent members of society: the ones who haven’t been born.”
Torche adds that it is somewhat surprising the study did not see a similar correlation between police shootings of Hispanic individuals and the health of Hispanic babies. Legewie says he is still interpreting this result, but he notes there is a longer history of interactions between African American communities and the police and more media coverage of police killings of black people. [730 words]
Source: Scientific American https://www.scientificamerican.com/article/police-killings-of-unarmed-black-americans-may-affect-health-of-black-infants/ | 
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发表于 2019-12-11 10:04:01
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