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 10, 2022
Respiratory diseases lower in homes with retrofitted insulation
Retrofitting home insulation can reduce the onset of chronic respiratory diseases such as asthma by up to 10 per cent, new University of Otago research shows.
The research, published in science journal Indoor Air, found insulation can also help to manage symptoms, with even greater gains in homes that also had heat pumps fitted.
Researchers from the He Kāinga Oranga – Housing and Health Research Programme at the University’s Wellington campus analysed pharmaceutical prescriptions that were dispensed to residents of more than 200,000 houses that received subsidised insulation through the EECA Warm-Up New Zealand: Heat Smart programme that ran between 2009 and 2014.
Results show the intervention group, which included people whose homes were insulated between 2009 and 2011, was 10 per cent less likely to develop chronic respiratory diseases when compared with a control group whose homes had no retrofitted insulation.
Children under the age of 15 were 15 per cent less likely.
Lead author Dr Caroline Fyfe says the results support other studies conducted by He Kāinga Oranga that show children are less likely to develop asthma symptoms when their home environment is warmer and less prone to damp and mould.
“We also know that the longer people are exposed to cold and damp housing the more likely they are to develop chronic respiratory disease, so it is particularly important that children have a healthy home environment,” Dr Fyfe says.
Researchers also discovered there was a 4 per cent relative reduction in medication for respiratory disease symptoms dispensed to the intervention group after insulation was retrofitted.
The reduction was 7 per cent when a low-emissions, energy efficient heater – mostly commonly a heat pump – was also installed.
Dr Fyfe says the study adds to an emerging body of evidence that new onset of chronic respiratory conditions, as well as exacerbation of pre-existing diseases, can be prevented, at least in part, by addressing some of the causes of cold damp housing in Aotearoa New Zealand.
“Most New Zealand houses are cold by international standards, and many were built before insulation was required.
“Retrofitting insulation is a relatively inexpensive way of not only making houses warmer and more affordable to heat but also healthier to live in.”
(SACRAMENTO, Calif.) —New research from the UC Davis Violence Prevention Research Program finds racial and ethnic differences in how extreme risk protection orders (ERPOs) are perceived and used in California. The study, published in Preventive Medicine, found Black Californians perceived ERPOs as less appropriate and were less willing to ask a judge to approve one. Black Californians were also less likely to have legal representation at an ERPO hearing.
ERPOs — also known as “red flag” laws — are a type of civil restraining order. They temporarily prevent individuals at high risk of harming themselves or others from having access to firearms. In California, ERPOs are known as gun violence restraining orders (GVROs).
Previous research suggests ERPOs can prevent firearm-related harm, but their impact on racial and ethnic equity is largely unknown. The study provides the first empirical assessment of potential sources of racial and ethnic inequity in ERPO perceptions and use. It also offers several recommendations to promote racial and ethnic equity.
“Most of the people who participated in the study’s survey, including majorities of all racial and ethnic groups, thought ERPOs were at least sometimes appropriate. And most were willing to personally ask a judge for an ERPO for a family member,” said Julia Schleimer, co-lead author and a research data analyst in the Department of Emergency Medicine at UC Davis Health.
Study examined survey data and court records
To examine potential inequities by race and ethnicity, the researchers used two complementary data sources: a 2020 survey of California adults and ERPO court documents for the first three years after California’s GVRO law went into effect (2016 to 2018).
The survey was completed by 2,870 participants. The sample size was weighted to be statistically representative of the adult population of California. Most survey participants had never heard of ERPOs or red flag laws.
They were asked about their willingness to ask a judge for an ERPO for a family member in response to different risk scenarios. Some of the described risk scenarios included a family member with dementia, a family member having a mental health crisis, and a family member threatening harm to themselves or others.
Black participants were most likely to say they were not willing to ask a judge for an ERPO in all the described risk scenarios. They were also substantially less likely to say they preferred to have the police petition for an ERPO on their behalf. Black survey participants cited lack of knowledge and not trusting the system to be fair as their top reasons for being unwilling to seek out an ERPO.
ERPO-related court records showed:
No Black or Hispanic/Latinx individuals who were subject to an ERPO had family or household members submit the petition.
Compared with other racial/ethnic groups, Black and Hispanic/Latinx individuals subject to an ERPO were more often arrested at the time the order was served. This finding was partly explained by the higher proportion of assault-related (compared to self-directed) threats among these groups.
Black respondents were also the least likely to have documented firearm access and legal representation at the ERPO hearing.
Veronica Pear, a co-lead author of the study and an assistant professor in the Department of Emergency Medicine at UC Davis Health, noted, “The findings suggest new directions for research, which should include engagement with Black and Hispanic/Latinx communities impacted by firearm violence. There is a need to identify barriers to and facilitators of ERPO use. Future research should also seek to understand the relationship between ERPOs and arrests, clarifying what charges are brought concurrently with the ERPO and whether the ERPO service leads to arrest or vice versa.”
Recommendation to reduce inequity
“Ensuring that ERPOs do not reproduce racial-ethnic inequities in structurally rooted risk factors for violence and trauma will be critical to their effectiveness within a broader community safety ecosystem,” said Nicole Kravitz-Wirtz, senior author of the study and an assistant professor with the Violence Prevention Research Program.
The researchers suggestracial and ethnic equity in ERPO use may be improved by:
reducing barriers to petitioning
incorporating non-law enforcement intervention professionals like behavioral health specialists into the ERPO process
providing legal assistance to respondents and petitioners
investing in the social safety net
“ERPOs show promise in preventing firearm violence, but it is important to monitor whether the benefits and potential harms of ERPOs are distributed equitably and amend the policy or its implementation as needed,” Schleimer said.
Additional authors include A.J. Aubel, S. Buggs, R. Pallin, A.B. Shev, E. Tomsich and G.J. Wintemute from the UC Davis Violence Prevention Research Program, and C.E. Knoepke from the University of Colorado School of Medicine.
INSTITUTE OF ATMOSPHERIC PHYSICS, CHINESE ACADEMY OF SCIENCES
IMAGE: EFFECT OF TERRAIN ON AIR POLLUTION OVER THE NORTH CHINA PLAIN REGIONview more
CREDIT: JINGYI LIU
The North China Plain (NCP), one of the world's most polluted regions, is frequently engulfed by severe haze in the cold season, which has aroused broad public concern because of the adverse impacts on air quality, atmospheric visibility, and human health. Previous research has shown that the distinctive topography around the NCP favors air pollution via unfavorable meteorological conditions such as atmospheric stagnation; however, our understanding of the effects on atmospheric physical and chemical processes and their interactions is still limited.
Prof. Xin Huang and her research group from Nanjing University, China, explored the impact of complex terrain on the occurrence and evolution of haze pollution in the highly polluted NCP region by integrating in-situ observations and meteorology–chemistry modeling. They found that the complex terrain can greatly enhance secondary haze formation by blocking and lifting near-surface air pollutants and accelerating their chemical transformation. Worse still, the thick haze aloft can further intensify the interaction between aerosols and the planetary boundary layer (PBL) via heating the upper air and cooling the surface, which leads to more stagnant air and forms a positive feedback loop. These terrain-induced intensive interactions of physical and chemical processes of atmospheric aerosol jointly contribute to the relatively more severe haze pollution in the NCP region. The findings have been recently published in Atmospheric and Oceanic Science Letters.
“During haze events, cities located near the complex terrain frequently suffer from severe pollution because of the blocking effect of the mountains. This leads to atmospheric stagnation, which favors the continuous accumulation of freshly emitted pollutants near the ground surface,” explains Prof. Huang.
Considering severe pollution events in northern China are to a large extent driven by the formation of secondary aerosol, the team further analyzed the evolution of secondary pollution in the uplifted polluted air mass. They found that the main secondary inorganic aerosol accounted for over 70% of the fine particulate matter mass concentration during a heavy pollution episode.
“The upper air always features stronger oxidizing capacity compared to the ground surface, especially during wintertime. In this case, the uplifted primary pollutants can be readily oxidized in the upper air, which exacerbates the secondary aerosol formation,” outlines Prof. Huang. “Eventually, vertical mixing and deposition of secondary pollutants will further lead to the aggravation of pollution on the ground.”
This study also points out that the effect of terrain on pollution can be accompanied by intense aerosol–PBL interactions. During uplift-polluted days, the temperature stratification in the lower troposphere is significantly modified.
Based on online meteorology–chemistry coupled modeling, the team's work further indicates that the aerosol-induced upper-air heating and surface dimming effects stabilize the atmospheric stratification and lead to about a 50% drop in the PBL height, which further aggravates the air pollution.
By expounding the mechanism underlying the effect of complex terrain on pollution in the North China Plain region, this research emphasizes the importance of such an effect on the intense interaction between atmospheric physical and chemical processes. It could be a crucial factor for the frequent occurrence of air pollution in mountainous and coastal areas near complex topography.
INSTITUTE OF ATMOSPHERIC PHYSICS, CHINESE ACADEMY OF SCIENCES
More frequent extreme climate events have become a major global challenge. To mitigate the human and economic costs of these events, climatologists consistently create future climate predictions. These projections help policy makers develop actionable climate policies to avoid the most dangerous climate change effects. Because of the high data volume required for accurate forecasts, scientists rely on supercomputer-run climate models to make predictions and to project changes in the climate system. However, an incomplete physical understanding of the Earth’s dynamic climatic processes remains a major limitation regarding climate model usability.
Chibuike Ibebuchi from the Institute of Physical Geography, University of Würzburg, conducted a recent study, published in Advances in Atmospheric Sciences, which applied a synoptic climatological statistical modelling approach called “circulation typing with fuzzy rotated principal component analysis.” This new technique is designed to enhance the physical understanding of the mechanisms through which teleconnections, such as the sub-tropical Indian Ocean Dipole, impacts seasonal rainfall variability in southern Africa, a region that is vulnerable to climate extremes. Circulation typing considers both space and time for rainfall anomalies.
Ibebuchi believes that climate modeling and projection improvements can advance with more research studies that aim towards gaining a better physical understanding of climate processes on the synoptic and global scales. Furthermore, research should analyze how the synoptic and large-scale climate processes interact with regional climates. Researchers can achieve this by enhancing techniques for effectively breaking down climate data sets through space and time to unravel the distinct (continuous) variability associated with the climate system.
More specifically, for these subsequent studies, Ibebuchi aims toward developing and optimizing existing statistical methods for decomposing, or breaking down data sets to unravel physically meaningful climate forecasting signals. This includes diagnosing misrepresentations in climate modeling processes.
Tuebingosaurus maierfritzorum lived about 203 to 211 million years ago in the region now known as Swabian Alb and was a herbivore. The new species displays similarities with the large long-necked dinosaurs known as sauropods, and was identified when already-known dinosaur bones were re-examined. The results have been published in the open-access, peer-reviewed scientific journal Vertebrate Zoology.
The fossils, which are part of Tübingen’s paleontological collection, were previously interpreted as belonging to the family Plateosauridae. Now, in a large-scale project, scientists Dr. Omar Rafael Regalado Fernandez and PD Dr. Ingmar Werneburg have re-examined all dinosaur bones stored in Tübingen. Most of the fossils originate from a quarry near Trossingen at the edge of Swabian Alb, where many dinosaur bones found since the 19th century have frequently been classified as Plateosaurus.
While it is undisputed that this group of dinosaurs was very common in parts of Europe about 200 million years ago, contemporary paleontologists are well aware that taxonomical classification in the past was often inaccurate, with some discoveries being too rapidly attributed to the Plateosaurus genus.
When they re-analyzed a skeleton that was discovered in Trossingen in 1922, consisting mainly of the rear of the body, Regalado Fernandez and Werneburg established that many of the bones were not the same as a typical Plateosaurus.
For instance, the partial skeleton displayed, among other derived characters, demonstrates broader and more strongly-built hips with fused sacral vertebrae, as well as unusually large and robust long bones. Both features imply locomotion on four legs. This is unlike the plateosaurid dinosaur, which - although resembling the long-necked sauropods from the Jura region - likely moved on only two legs.
Following in-depth comparison of all anatomical characteristics, the scientists re-categorized the partial skeleton from Trossingen in the dinosaur tree of life and established that they had discovered a previously unknown species and genus.
It is highly probable that the newly described Tuebingosaurus maierfritzorum was a quadruped, hence, far more closely related to more recently lived large sauropods, such as Brachiosaurus or Diplodocus.
The surrounding sedimentary rock and the preservation of the bones indicate that this Tuebingosaurus had sunk into a swamp and died. The bones on the left side of the body were probably on the surface and exposed to the elements for several years.
“Its genus name, Tuebingosaurus, is a homage to our beautiful university city and its inhabitants,” says Werneburg.
The species name (maierfritzorum) is a tribute to two German zoologists: Professor Wolfgang Maier from Tübingen and Professor Uwe Fritz from Senckenberg Natural History Collections Dresden.
In summary, with their project, the scientists demonstrate that the early European dinosaurs were far more diverse than previously thought.
After completing the study of the skeleton of the newly discovered species Tuebingosaurus maierfritzorum, the bones were put back together and can already be seen in two large display cabinets in the Tübingen’s paleontological collection.
There, amongst the thousands archaeological finds, the visitors can also find two complete Plateosaurus skeletons from Trossingen, partial skeletons of two sauropods and one stegosaur from Tanzania.
Reconstruction of how the death of the Tuebingosaurus maierfritzorum specimen may have occurred. Bones of the predatory dinosaur Teratosaurus were also found in Trossingen. However it has only been proven that Tuebingosaurus fell on its right side. Weathering indicates that the bones on the left side of the body probably lay for several years on the surface.
CREDIT
Marcus Burkhardt
Ingmar Werneburg (left) and Omar Rafael Regalado Fernandez (right) in the archive of the paleontological collection at Tübingen. The hips of Tuebingosaurus maierfritzorum can be seen in the foreground.
CREDIT
Valentin Marquardt and University of Tübingen
Research article:
Regalado Fernández OR, Werneburg I (2022) A new massopodan sauropodomorph from Trossingen Formation (Germany) hidden as 'Plateosaurus' for 100 years in the historical Tübingen collection. Vertebrate Zoology 72: 771–822. https://doi.org/10.3897/vz.72.e86348
A new massopodan sauropodomorph from Trossingen Formation (Germany) hidden as 'Plateosaurus' for 100 years in the historical Tübingen collection.
ARTICLE PUBLICATION DATE
8-Sep-2022
Eating behaviors of parents play a role in teens' emotional eating
New study published in the Journal of Nutrition Education and Behavior outlines what role parents can play in shaping emotional eating in their adolescent children
AUDIO: LEAD AUTHOR JOANNA KLOSOWSKA, MSC, DISCUSSES A NEW STUDY FOCUSING ON ADOLESCENT VULNERABILITY TO EMOTIONAL EATING AND HOW VARIOUS FEEDING PRACTICES USED BY PARENTS, SUCH AS RESTRICTION, FOOD AS REWARD, AND CHILD INVOLVEMENT, INFLUENCE EATING BEHAVIOR.view more
CREDIT: JOURNAL OF NUTRITION EDUCATION AND BEHAVIOR
Philadelphia, September 7, 2022 – Emotional eating, or eating as a coping mechanism for negative, positive, or stress-driven emotions, is associated with unhealthy dietary patterns and weight gain. A research article featured in the Journal of Nutrition Education and Behavior, published by Elsevier, discusses adolescent vulnerability to emotional eating and how various feeding practices used by parents, such as restriction, food as reward, and child involvement, influence eating behavior.
"Emotional eating was previously found to be more learned than inherited. This study examined not only the interaction between parents when feeding their children, but also what children learned from watching their parents eat," said lead author Joanna Klosowska, MSc, Department of Public Health and Primary Care, Ghent University, Ghent, Belgium.
The initial study was conducted in 2017 with 218 families. Additionally, longitudinal data collected in 2013 were also available. One parent from each family completed the Child Feeding Questionnaire, as well as the Child Feeding Practices Questionnaire, and both adolescent and parent completed the Dutch Eating Behavior Questionnaire. Emotion regulation was assessed with the Dutch version of the child-reported FEEL-KJ questionnaire. The adolescent's body weight and height were measured by researchers.
Over the four years between 2013 −2017, covering the time from late childhood to middle adolescence, changes occurred in some parental practices. Parents reported higher monitoring and healthy modeling feeding practices, while the reported levels of food restriction and the healthy environment remained unchanged. During the same time period, adolescents reported a considerable increase in emotional eating from below the average in 2013 to above the average in 2017, according to the norms for the Dutch population. Additionally, the maladaptive way in which they regulated their emotions was also associated with emotional eating.
Food as a reward and monitoring food increased emotional eating especially in instances where the adolescent employed maladaptive strategies in regulating their emotions. Child involvement in meals had an opposite effect since it was associated with higher levels of emotion regulation and lower levels of emotional eating. Interestingly, a parent's restrained eating behavior was linked to less emotional eating in adolescents.
"This study suggests that parents continue to play an important role in their child's eating behavior into their teen years," said Klosowska. "Additional research is needed to understand the impact restrained eating demonstrated by a parent impacts the emotional eating of a child."
Emotion Regulation Moderates the Associations of Food Parenting and Adolescent Emotional Eating
ARTICLE PUBLICATION DATE
7-Sep-2022
Dedicated women’s heart centers can improve accurate diagnoses and outcomes
Important study in the Canadian Journal of Cardiology showcases improvement in outcomes for women with ischemic heart disease by attending a multidisciplinary women’s health center
IMAGE: THE OBJECTIVE OF THIS STUDY WAS TO INVESTIGATE WHETHER ATTENDING A WOMEN’S HEART CENTER IMPROVES DIAGNOSIS AND OUTCOMES IN WOMEN WITH INOCA AND MINOCA. INOCA: ISCHEMIA WITH NO OBSTRUCTIVE CORONARY ARTERY DISEASE; MINOCA: MYOCARDIAL INFARCTION WITH NO OBSTRUCTIVE CORONARY ARTERY DISEASE.view more
CREDIT: CANADIAN JOURNAL OF CARDIOLOGY
Philadelphia, September 7, 2022 – Cardiac conditions in women are underdiagnosed, undertreated, and under-researched compared to men. In an important prospective study in the Canadian Journal of Cardiology, published by Elsevier, investigators report that attending a multidisciplinary dedicated women’s heart center can increase the likelihood of an accurate diagnosis and significantly improve clinical and psychological outcomes of women reporting chest pain due to insufficient heart-muscle blood flow (myocardial ischemia) but not diagnosed with obstructive coronary artery disease.
Cardiovascular disease (CVD) continues to be a leading cause of hospitalization and death in women. Declines in CVD death rates have stalled in mid-life women compared to men, suggesting sex-specific approaches may be needed.
Many women with cardiac chest pain and ischemia or myocardial infarction do not have significant blockages in the arteries supplying the heart (obstructive coronary artery disease). Ischemia with no obstructive coronary artery disease (INOCA) may affect up to 62% of women undergoing coronary angiography for suspected angina, with a higher prevalence in mid-life women aged 45-65 years. Myocardial infarction with no obstructive coronary artery disease (MINOCA) accounts for 6% of myocardial infarctions and is more frequently diagnosed in women. Studies suggest that patients with INOCA and MINOCA have a decreased quality of life and are at increased risk of cardiovascular events like heart attacks and acute heart failure.
"Most studies of heart health consist primarily of male participants, and numerous clinical outcomes such as patient symptoms and treatments do not therefore necessarily apply to women with certain types of heart disease,” explained lead investigator Tara L. Sedlak, MD, Vancouver General Hospital Department of Cardiology, University of British Columbia Faculty of Medicine, and British Columbia Women’s Hospital, Vancouver, BC, Canada. “We conducted this research to gain a better understanding of the etiologies and treatment of women with ongoing signs and symptoms of INOCA, which is one of these understudied areas in heart health.”
Investigators prospectively followed 154 patients (112 INOCA and 42 MINOCA patients). attending the women’s heart center at Vancouver General Hospital, who completed baseline demographics questionnaires. Median age was 59, and the most common referral was for chest pain (94% in INOCA and 66% in MINOCA). After one year, chest pain frequency, quality of life, depression/anxiety symptoms, and cardiovascular outcomes were compared to baseline.
Many women with cardiac chest pain and ischemia or heart attack have no significant blockages of their larger coronary arteries but can have narrowing or dysfunction of their small coronary vessels or spasm of their blood vessels, which may be missed at initial diagnosis.
At baseline, 64% of INOCA and 43% of MINOCA patients did not have a specific diagnosis. Following investigations in the center, 71% of INOCA patients established a new or a changed diagnosis (the most common of which was coronary microvascular dysfunction at 68%), while 60% of MINOCA patients established a new or change in diagnosis (the most common of which was coronary vasospasm at 60%). At one year, participants had significantly decreased chest pain, improved quality of life and improved mental health.
“To our knowledge, this is the first prospective report of the outcomes in Canadian women with chest pain who have attended a women’s heart center,” noted Dr. Sedlak. “We hope our findings highlight the importance of having a dedicated women-specific heart center, which provides comprehensive care for women with heart disease by providing risk factor assessment, referral to psychiatrists, exercise classes, smoking cessation treatment, and consultation with a dietitian in addition to a focus on conditions such as INOCA that are more common in women.”
In an accompanying editorial, C. Noel Bairey Merz, MD, Barbra Streisand Women’s Heart Center in the Smidt Heart Institute at Cedars-Sinai, Los Angeles, CA, USA. and colleagues congratulate Dr. Sedlak and coinvestigators on this important study as one of the first in Canada to showcase the improvement in outcomes for women with INOCA or MINOCA through a specialized women’s health center.
“These centers and programs continue to increase awareness, improve education for patients and healthcare providers, and facilitate accessibility to specific diagnosis, risk stratification, and management. Furthermore, as illustrated by this study, the multidisciplinary foundation of these centers fosters collaborations across the various disciplines that provide care for women, bridging the continuity between advocacy, research, and clinical expertise, Dr. Merz commented. “With the growing momentum from the last three decades, specialized women’s health centers are increasingly recognized as a long-term, sustainable model to address ongoing disparities facing women with cardiovascular risk factors and disease.”
IMAGE: ONCE IN A CENTURY FLOWERING AND SEEDING OF DWARF BAMBOO BOOSTS MICE POPULATIONSview more
CREDIT: REIKO MATSUSHITA
A research group from Nagoya University in Japan has found that an event that occurs only once every 120 years, the large-scale flowering, seeding, and dying of dwarf bamboo (Sasa borealis), provides ideal breeding conditions for Japanese field mice.
The large-scale flowering and seeding of dwarf bamboo is a rare event. This plant phenomenon is called masting, and the next one is not expected for more than 100 years. During such events, which occur in “mast years”, some plants will produce heavy seed crops. Plants that coordinate their flowering and fruiting in mast years do so simultaneously and over a wide area.
Rodent outbreaks are believed to be associated with feeding on bamboo seeds in these mast years. This has received a lot of attention because of the agricultural and forest damage that occurs, as well as the risk of diseases spread by these rodents. There have been previous reports of large-scale tree mortality during such events due to rodent outbreaks.
In the 2010s, the masting of dwarf bamboo, a Sasa species with a 120-year masting cycle, began to be observed on forest floors throughout Japan. A team of researchers from Nagoya University led by Associate Professor Hisashi Kajimura and doctoral student Hanami Suzuki, both from the Graduate School of Bioagricultural Sciences, investigated the effects of this simultaneous seeding of dwarf bamboo on local rodent populations in Aichi Prefecture, Japan. Comparing data from before and after the masting, the researchers found an increase in the populations of both the large and small Japanese field mouse, but no similar effect was seen on Smith’s voles in the same area. Their results were published in Ecological Processes.
“The interesting biological phenomenon that masting of bamboo and dwarf bamboo can cause an outbreak of forest rodents has long been something of a legend,” says Kajimura. “This research is important because it clarifies this long-suspected phenomenon by comparing rodent populations before and after masting.”
“What was interesting was that the increased populations of both species of rodent that we studied remained even two years after the masting, even though the dwarf bamboo itself had died.” explains Suzuki. “There was also a high proportion of female juveniles in the population, suggesting that the simultaneous fruiting resulted in good conditions for reproductive females. These findings clearly show for the first time how the field mouse population responds to the seeds of Sasa, such as dwarf bamboo, especially those that have a longer cycle and larger supply.”
The team is excited about the implications of their study. “This research is expected to provide important clues for understanding the realities of sudden environmental changes in forest ecosystems and the interactions among the organisms that live there,” they said.
This research was supported by the Nagoya University Fusion Frontier Fellowship Program, which began in FY2021.
IMAGE: PAROTOID GLAND SIZES OF URBAN POPULATIONS WERE SIGNIFICANTLY SMALLER THAN THOSE IN RURAL POPULATIONS, WHEREAS BODY MASS DID NOT DIFFER. LEG LENGTHS OF URBAN MALES WERE LONGER THAN THOSE OF RURAL MALES, BUT URBAN FEMALES HAD SHORTER LEGS THAN RURAL FEMALES. THESE RESULTS DEMONSTRATE THAT URBANIZATION CAUSES MORPHOLOGICAL CHANGES IN INVASIVE TOADS.view more
CREDIT: HIROTAKA KOMINE, YAMAGATA UNIVERSITY
Biodiversity is increasingly diminished by humanity’s many impacts, a major aspect of which is urbanization. Although there are a lot of studies reporting that urbanization influences wildlife population sizes and distributions, we are only beginning to study urbanization as an evolutionary force. Urban environments are also hotspots for invasive species, i.e., species that are not indigenous, or native, to an area, which can cause significant economic and ecological damage. In addition, invasive species provide an evolutionary laboratory in which we can study the effects of urbanization.
Cane toads are invasive in Australia, and Assistant Professor Hirotaka Komine with the Tokyo University of Agriculture and Technology (Current affiliation: Yamagata University) along with colleagues from Australia’s James Cook University, wanted to find out whether the urban environment had impacts on the morphology of these toads. They hypothesized that toads may have fewer predators in urban environments compared to ‘country’ or peri-urban environments, and that this may mean that urban toad antipredator defences were less well developed.
They published their findings on 2 September 2022 in Biological Journal of the Linnean Society.
They captured 419 adult toads in 3 Queensland Australian towns: Townsville, Cairns and Mackay, within city limits, and then ventured to surrounding rural areas of each city. They measured these toads’ parotoid glands, which contain strong toxins for anti-predator defense, as well as leg length and mass.
The researchers found parotoid gland sizes were significantly smaller in urban toads compared to those in rural populations, although body mass was not different. Interestingly, leg lengths of urban males were longer than those of rural males, but the legs of urban females were shorter than rural females. Thus, urbanization caused reduced anti-predator defenses in invasive toads, and also increased sexual dimorphism in leg length. Invasive toads were introduced to Australia in 1935, so these morphological changes may have occurred rapidly. Without genetic work, we do not know if these changes are a phenotypically plastic response, or genetically encoded, but in either case they seem adaptive.
“This invasive species could apparently adapt rapidly to the urban environment,” said conservation biologist Hirotaka Komine. “Phenotypic changes in invasive species could enhance their invasiveness, so these findings are not only interesting for evolutionary biologists, but could also be valuable for conservation of native ecosystems.”
The researchers added that further studies are needed to reveal the underlying mechanism driving these morphological changes and to clarify whether these changes were evolutionary or phenotypic changes.
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Original publication:
Komine, H. *, Yasumiba, K. & Schwarzkopf L. The country toad and the city toad: comparing morphology of invasive cane toads (Rhinella marina) from rural and urban environments. Biological Journal of the Linnean Society, blac100 https://doi.org/10.1093/biolinnean/blac100 *: corresponding author
