We can “teach” corals how to withstand the increasing temperature
- Global warming is the greatest threat to coral reefs.
- Projects about coral restoration have expanded around the world to replenish habitats with corals affected by different stressors.
- However, these restoration efforts will be of no use if outplanted corals cannot withstand the warmer oceans and high-temperature events.
- Stress hardening is one of the approaches to increase the temperature tolerance of corals currently grown for restoration.
- Scientific evidence suggests that environments with varying temperatures can reduce coral bleaching during exposure to thermal stress.
- However, it is still unclear if this localized adaption to varying temperatures can be used to enhance coral restoration efforts.
- Researchers treated fragments of Caribbean staghorn coral with variable and static temperatures in the laboratory for 89 days.
- The variable temperatures oscillated two times per day from 28 °C to 31 °C, while the static temperature was set to 28 °C.
- The fragments were then exposed to heat stress at 32 °C for 2 weeks.
- Corals in the variable temperatures showed signs of severe thermal stress later than corals in the static temperature and untreated field controls.
- Additionally, corals in the field control groups showed a higher incidence of tissue degradation while corals in the variable temperatures give way to bleaching at a slower pace.
- The study highlights the importance of variable temperature exposure to improve thermal tolerance of corals.
- The discovery will be important for future research and restoration of corals affected by climate change.
DeMerlis, A., Kirkland, A., Kaufman, M.L. et al. Pre-exposure to a variable temperature treatment improves the response of Acropora cervicornis to acute thermal stress. Coral Reefs (2022). https://doi.org/10.1007/s00338-022-02232-z
Pfizer’s paxlovid drug has the potential to treat high-risk COVID-19 patients
- Paxlovid is an investigational antiviral drug used to treat COVID-19 in both adults and children.
- Pfizer’s oral version of paxlovid significantly reduced hospital admissions and deaths in people infected with SARS-CoV-2.
- The study included 1219 adults who were registered by September 29, 2021.
- Participants who received paxlovid within 3 days of the onset of COVID-19 symptoms had an 11 percent chance of getting admitted to a hospital or death related to COVID-19.
- In contrast, participants who received the placebo had an 89 percent chance for the same consequences.
- Paxlovid contains two medications namely nirmatrelvir and ritonavir which are protease inhibitors.
- Participants treated with paxlovid within 5 days of the onset of symptoms had only 1 percent chance of getting admitted up to day 28 with no deaths while participants in the placebo group had 6.7 percent with 10 deaths.
- Safety analysis revealed that people treated with paxlovid had 1.7 percent chance of experiencing serious adverse events while people treated with placebo had 6.6 percent chance.
Mahase E. (2021). Covid-19: Pfizer’s paxlovid is 89% effective in patients at risk of serious illness, company reports. BMJ (Clinical research ed.), 375, n2713. https://doi.org/10.1136/bmj.n2713
Pet food products may contain endangered shark species
- Sharks existed long before the time of the dinosaurs.
- These predators that are important to the natural order of marine ecosystems now face their most serious threat.
- For the past 50 years, shark populations have declined by more than 70 percent.
- Overfishing has been speculated to be the reason for the decline.
- There is an increased public awareness regarding shark conservation; however, about 75 percent of all marine shark species are considered at risk of extinction.
- Researchers identified shark DNA in pet food available in Singapore.
- The blue shark is the most common shark identified in the pet food.
- Although not classified as threatened by IUCN, blue sharks have been overexploited according to scientific evidence and should have been protected.
- The second most commonly identified are the silky sharks.
- These pet food products do not list sharks as ingredients instead, they show terms such as “white fish”, “white bait”, and “ocean fish.”
- The vague terminology in the ingredients and mislabeling of contents prevents consumers from making informed and environmentally conscious decisions.
- As a result, consumers such as pet owners and animal lovers may unintentionally be contributing to the overfishing of sharks.
Frontiers in Marine Science (2022). www.frontiersin.org/articles/1 … ars.2022.836941/full
Female chimpanzees keep themselves away from humans
- Human activities can cause rapid changes in the environment.
- Large animals are likely to survive in this rapidly changing environment as long as they have high levels of behavioral flexibility.
- Chimpanzees are animals that form close-bonded social groups and display high fission-fusion dynamics.
- Fission-fusion dynamics is a property of social system that displays time-related variation in cohesion, subgroup size and composition.
- Researchers examined the social responses in chimpanzees to determine the animal’s resilience to dynamic human activities and improve human-wildlife interactions.
- Researchers studied the social adjustment of chimpanzees to risks introduced by human-modified landscape in Uganda.
- The study occured simultaneously with the seasonal availability of cultivated jackfruit.
- Jackfruit is a dominant tropical fruit that can be found in croplands and village garden.
- The party size of chimpanzees decreased when they moved from low-risk natural habitat to high-risk habitat such as croplands and village regions, driven mostly by parties with fewer females.
- Researchers found that the chimpanzee social structure showed partial flexibility in response to human activity risk.
- Males were more central than females in high-risk habitat.
- Sex differences were observed to be driven by changes to membership between habitat types.
- The study suggests that human activity risk can trigger repeated adjustments to chimpanzee groups in response to changing environment that modify the social lives of chimpanzees in various ways.
- As a result, grouping pattern changes caused by human-induced activity could impact ecological and evolutionary processes triggered by social structure, including the spread of infectious disease.
Zoe M. Satsias et al. (2022). Sex-specific responses to anthropogenic risk shape wild chimpanzee social networks in a human-impacted landscape, Animal Behaviour. DOI: 10.1016/j.anbehav.2022.01.016
Earthworms can enrich the soil, faster than previously thought
- Nutrient cycling is a process by which nutrients are transferred from the environment to living organisms and back to the environment.
- Usually, nutrient cycling involving soil decomposers, such as earthworms, is slow and cumulative.
- Researchers show that it is possible to have a rapid movement of nitrogen and carbon from earthworms to plants and herbivores.
- They performed two experiments, one under a laboratory and the other in the field.
- Researchers used chemical tracers to monitor the movement of nutrients from earthworms to the soil, plant seedlings, and sap-sucking bugs.
- Nitrogen and carbon derived from the earthworms were obtained by the bugs after only two hours under laboratory conditions, and nitrogen after 24 hours in the field.
- Researchers speculated that the source of this nitrogen and carbon was the earthworms’ labeled mucus on their skin.
- Based on the rapid tracer appearance in herbivores, researchers suggest that an amino acid compound excreted by earthworms may have been involved.
- The results suggest a previously unknown shortcut in the nitrogen and carbon cycle.
Ganna S. Shutenko, G. S. Shutenko, Walter S. Andriuzzi, W. S. Andriuzzi, Jens Dyckmans, J. Dyckmans, Yu Luo, Y. Luo, Thomas L. Wilkinson, T. L. Wilkinson, & Olaf Schmidt, O. Schmidt. (2022). Rapid transfer of C and N excreted by decomposer soil animals to plants and above-ground herbivores. Soil biology & biochemistry, 166, 108582. doi: 10.1016/j.soilbio.2022.108582
Severed pieces of planarian behave like a whole animal
- Planarian is a free-living flatworm known for its soft, broad, leaf-shaped ciliated body and a three-branched digestive tract.
- Planarian is well-known for its regeneration capabilities.
- The behaviors of freshwater planarians have been extensively studied for many years.
- Planarian behavior has been used to study the animal’s development, regeneration, molecular evolution, memory, and many more.
- The nervous system of the planarian is one of the simplest of bilaterally symmetric animals.
- Bilateral symmetry is an animal with body shapes that are mirror images along a midline, such as a butterfly.
- Planarian has an anterior brain connected to ventral nerve cords interconnected by multiple commissures.
- Commissures are nerve tissues that connect the hemispheres of the brain and the two sides of the spinal cord.
- Researchers found that when an intact planarian is stimulated by mechanical means and electromagnetic radiation, the head turns, the tail contracts, and the trunk elongates.
- When the planarian was cut into three pieces, the front of the headless middle part behaved like the head and started to turn instead of elongating.
- Additionally, the end of the head and midbody sometimes contracts instead of elongating.
- Each of the body pieces seems to behave like a whole animal.
- The results suggest that the planarian nervous system can quickly reorganize to fix functional problems complementing the slower regeneration processes.
- The reorganization allows the planarian to survive while regenerating the other tissues.
Le, D., Sabry, Z., Chandra, A., Kristan, W. B., 3rd, Collins, E. S., & Kristan, W. B., Jr (2021). Planarian fragments behave as whole animals. Current biology : CB, 31(22), 5111–5117.e4. https://doi.org/10.1016/j.cub.2021.09.056
Research Highlights: Successful development of lake whitefishes depends on a narrow range of temperature
Successful development of lake whitefishes depends on a narrow range of temperature
- Lake whitefish is a species of freshwater fish found in North American lakes including all of the Great Lakes.
- It is considered highly valuable in commercial fishing and occasionally used in sports fishing.
- Lake whitefish embryos usually develop during the winter season; thus, these embryos may be susceptible to changes in temperature.
- Researchers incubated whitefish embryos in different but constant temperatures and in varying temperatures.
- They discovered that hatchlings had a lower survival rate in 8 °C and varying temperatures than in 2 °C and 5 °C temperatures.
- Additionally, lake whitefish eggs tend to hatch earlier in 8 °C and varying temperatures compared to eggs in 2 °C and 5 °C temperatures.
- Researchers also found that hatchlings in 8 °C and varying temperatures were significantly smaller than in 2 °C and 5 °C temperatures.
- The study highlights the effect of temperature during embryonic development in lake whitefishes.
Eme, J., Mueller, C. A., Lee, A. H., Melendez, C., Manzon, R. G., Somers, C. M., Boreham, D. R., & Wilson, J. Y. (2018). Daily, repeating fluctuations in embryonic incubation temperature alter metabolism and growth of Lake whitefish (Coregonus clupeaformis). Comparative biochemistry and physiology. Part A, Molecular & integrative physiology, 226, 49–56. https://doi.org/10.1016/j.cbpa.2018.07.027
Millipedes ingest food using a sucking pump
- Sucking liquid food is common among certain insects such as the nectar-sucking butterflies and blood-sucking mosquitoes.
- This food-sucking mechanism has been observed in tardigrades, velvet worms, spiders, crustaceans, and insects.
- Millipedes are a group of invertebrates having two pairs of legs on most of their segment.
- Researchers discovered a fluid feeding mechanism using a sucking pump among millipedes.
- They studied nine millipede species in the clade Colobognatha and found that the head of these millipedes has a pumping chamber.
- Colobognatha has been suspected to have a food-sucking mechanism because of their pointed heads and the largely reduced mandibles.
- The pumping chamber acts as a positive displacement pump which is similar to other insects.
- A positive displacement pump is a pump that adds energy to a fluid by applying force to the liquid using either a piston or plunger.
- The millipede’s sucking pump works with protractible mouthparts and saliva to acquire liquid food.
- Fluid feeding is one of the great capabilities of land invertebrates.
- The study suggests that fluid feeding evolved with similar biomechanical solutions convergent across major invertebrate taxa.
- Fluid feeding among insects is highly diverse today; however, it is still unclear why other invertebrates such as Colobognatha contain only a few food-sucking species.
Moritz, L., Borisova, E., Hammel, J. U., Blanke, A., & Wesener, T. (2022). A previously unknown feeding mode in millipedes and the convergence of fluid feeding across arthropods. Science advances, 8(7), eabm0577. https://doi.org/10.1126/sciadv.abm0577
On Going Research: CSUSM researchers seek to understand antibiotic resistance among microbes in coastal areas
CSUSM researchers seek to understand antibiotic resistance among microbes in coastal areas
- Antibiotic resistance occurs when bacteria tolerate the presence of a drug because of some gene mutations.
- Antibiotic resistance is currently a threat to global health.
- Microbial antibiotic resistance can spread from one microbe to another through horizontal gene transfer.
- Horizontal gene transfer is the transfer of genetic materials from one bacteria to another bacteria rather than DNA transfer from parent or offspring as in reproduction.
- The use of antibiotics has been shown to foster an antibiotic-resistant microbial population.
- The coasts are particularly at risk because of human inputs such as sewage, agricultural contaminants, and climate change.
- These human inputs can affect the transmission of antibiotic resistance genes.
- A group of researchers from California State University San Marcos led by Professor Elinne Becket seek to understand the transmission of antibiotic resistance genes among microbes in coastal regions.in response to commonly known antibiotics observed in agricultural and city waste.
Brushfire Affects Soil Microbial Abundance and Enzymatic Activities For Years
- Soil microbes are important in maintaining soil processes such as litter decomposition, nutrient cycling, and plant growth.
- However, there is a lack of understanding about the effect of fire and post-fire management methods on the population and activities of soil microbes.
- A group of researchers from the California State University-San Marcos examined surface soil from unburned, burned and naturally regenerating, and burned but hydroseeded chaparral areas.
- Hydroseeding is the process of spraying a watery mixture of seeds, mulch, and fertilizer.
- The sampling site is within the campus of California State University-San Marcos and had an incident of fire five years ago.
- Researchers analyzed microbial biomass carbon, phylum-level bacterial taxonomic composition, and microbial activities.
- They tried to test if fire and hydroseeding affect the population and activities of soil microbes.
- Researchers discovered that in burned areas, total soil nitrogen and carbon, microbial carbon, enzymatic activity, and nitrification rate are significantly lower compared to unburned areas.
- However, some of these observations were affected by hydroseeding.
- Changes in the composition of colonizing plants and carbon inputs from hydroseeding affected the soil carbon, soil nitrogen, and microbial carbon such that they were all similar in the burned hydroseeded areas and unburned areas.
- Furthermore, no significant differences in taxonomic diversity between the three areas.
- Key carbon cycling enzymes such as β-glucosidase and peroxidase, and nutrient cycling enzymes such as N-acetylglucosaminidase were significantly lower in burned areas.
- The activities of these key enzymes were not affected by hydroseeding and the declines were probably due to the declines in microbial abundance, soil carbon and nitrogen pools, and elevated pH.
- The results suggest that fire and post-fire treatments can affect the abundance and activities of soil microbes for years.
Vourlitis, George & Steinecke, Dylan & Martinez, Tanairi & Konda, Karen & Rendon, Roxana & Hall, Victoria & Khor, Sherryca & Sethuraman, Arun. (2022). Fire and post-fire management alter soil microbial abundance and activity: A case study in semi-arid shrubland soils. Applied Soil Ecology. 171. 104319. 10.1016/j.apsoil.2021.104319. https://doi.org/10.1016/j.apsoil.2021.104319