u/VCardBGone

Marine photosynthesis makes about half of Earth's annual oxygen flow. The number is real, but it measures production rather than a net annual refill of the atmosphere.

https://oceanservice.noaa.gov/facts/ocean-oxygen.html

https://www.science.org/doi/10.1126/science.281.5374.237

https://science.nasa.gov/earth/earth-observatory/what-are-phytoplankton/

https://science.nasa.gov/earth/earth-observatory/a-sea-aswirl-with-chlorophyll-154699/

https://www.alice.cnptia.embrapa.br/alice/bitstream/doc/1159190/1/Biogeochemical-cycles.pdf

https://scienceblog.com/t-earth-has-five-named-oceans-but-they-form-one-connected-system-covering-71-percent-of-the-planet-moving-heat-carbon-and-nutrients-between-basins-on-currents-that-can-take-a-millennium-to-circle-the/

Born in the monsoon lushness of 1997 to tigress Machli I, the cub designated 'T-16' was named Machli after her mother owing to the distinctive fish-shaped mark on the left side of her face.

Machli I seemed pre-ordained for sovereign rule. Yet, in the unforgiving theatre of Ranthambore, birthright yields to strength. In 1999, a young 'T-16' ousted her aging mother to claim the prime lakes—Padam Talao, Raj Bagh, and Malik Talao. She transformed the ancient Ranthambore Fort ruins into her personal ramparts, earning titles like Lady of the Lakes and Empress of Ranthambore.

Exactly a decade later, in 2009, the wheel of wild fate turned full circle: Machli's daughter, Sundari ('T-17'), defeated and displaced her.

While internet lore focuses on her dramatic fights, including her 2003 encounter wherein she single-handedly killed a 14-foot mugger crocodile (a fight that cost her two canines), tiger biologist and author Dr Latika Nath says that beneath the viral fame, Machli was simply "an extraordinarily successful wild animal".

Machli took over one of the richest territories in Ranthambore and held it for years against every challenger, proving that lasting dominance requires genuine strength and skill, Dr Nath adds. That tactical intelligence extended to her daily survival strategies.

Conservation biologist Vibhav Srivastava highlights Machli's rare behavioural adaptability, noting that "she learned to use safari vehicles as tactical cover while stalking prey, maintaining a bold, calculating presence in a landscape shared with humans."

https://en.wikipedia.org/wiki/Machali\_(tigress)

https://www.ranthamborenationalpark.com/ranthambore-machali.html

https://www.tigersafariindia.com/blog/machli-the-tigress-of-ranthambore/

https://science.thewire.in/environment/machli-tigress-ranthambore-conservation/

Like most jellyfish, Turritopsis starts as a fertilized egg, becomes a tiny swimming larva, settles on a rock and grows into a polyp colony. That colony buds off free-swimming medusae, the bell-shaped adults we picture when we hear the word jellyfish. Adults spawn, and the cycle begins again.

What the student saw was an adult medusa, stressed and starving in its dish, sinking to the bottom, collapsing into a blob of tissue and then reorganizing itself into a polyp. It had gone backwards. A few days later the polyp began budding out new medusae, each genetically identical to the adult that had dissolved. The American Museum of Natural History describes it as the animal hitting a reset button.

The mechanism is called transdifferentiation. Specialized adult cells such as muscle or nerve are converted directly into other cell types, without passing through a stem-cell stage. In principle a Turritopsis medusa can do this every time it is injured, starving or simply getting old, which is why it picked up its nickname. In practice most individuals in the wild are eaten or diseased long before they get the chance.

https://www.amnh.org/explore/news-blogs/immortal-jellyfish

https://link.springer.com/article/10.1007/s10530-008-9296-0

https://stories.tamu.edu/news/2026/02/19/a-tiny-jellyfish-may-be-hiding-the-blueprint-for-eternal-life/

https://en.wikipedia.org/wiki/Turritopsis\_dohrnii#:\~:text=Turritopsis%20dohrnii%2C%20commonly%20known%20as,in%20temperate%20to%20tropic%20waters.

Nature invented biodegradable plastic long before humans did—and animals may have been feeding on it for hundreds of millions of years. Researchers discovered that dozens of animal species possess enzymes capable of breaking down microbial bioplastics called PHAs, a talent once thought to belong only to microorganisms.

The gutless marine worm Olavius algarvensis (here lying next to some sand grains) is only about two centimeters long and has become so dependent on its bacterial symbionts for nutrition and waste recycling that it has lost both its digestive and excretory systems. Its white appearance comes from the dense layer of bacterial symbionts beneath its skin, which are packed with PHA, the microbial bioplastic at the center of this study. This inconspicuous worm helped scientists discover that animals can digest microbial bioplastics previously thought to be broken down only by microorganisms.

https://en.wikipedia.org/wiki/Polyhydroxyalkanoates

https://pmc.ncbi.nlm.nih.gov/articles/PMC8512352/

https://www.nature.com/articles/am201648

Artificial intelligence has designed viruses that can infect bacteria and reproduce – a first that shows AI is beginning to do more than analyse the genetic code of living things. It can write new versions of it, too.

The viruses in question are bacteriophages, or phages – viruses that infect bacteria rather than people, animals or plants. Researchers used AI to design hundreds of new versions of a well-studied phage, then built the viruses from scratch in the laboratory.

Of 285 AI-designed genomes that the team tested, 16 produced working phages capable of infecting E coli.

The result is an important step for a field sometimes called generative biology, in which AI is used to design new biological molecules and organisms. But it is also important to understand what the researchers have – and have not – demonstrated.

Phages are essentially bacterial predators. They are among the most abundant and diverse biological entities on Earth and have evolved alongside bacteria for billions of years.

Most phages are highly specialised. They recognise molecules on the surface of a bacterium, attach themselves and inject their genetic material inside. The phage then takes over the bacterium’s molecular machinery, using it to make new copies of itself. Eventually, the infected cell bursts, releasing the new phages.

https://www.science.org/doi/10.1126/science.aec2657

https://www.who.int/news-room/fact-sheets/detail/antimicrobial-resistance

For millions of Indians, railway stations are places where a basic need is taken for granted: finding safe drinking water. A recent Comptroller and Auditor General (CAG) audit, however, has raised questions about whether that assumption is always justified. Water samples from water coolers at eight railway stations across four zones tested positive for E. coli, according to the audit findings. The stations were Coimbatore and Palakkad Junctions in Southern Railway, Hyderabad in South Central Railway, Chhatrapati Shivaji Maharaj Terminus, Bhiwandi Road, Kalyan and Lonavala in Central Railway, and Madhupur in Eastern Railway.

https://indianrailways.gov.in/railwayboard/uploads/PDF/MX-M464N\_20230628\_143346.pdf

https://indianrailways.gov.in/railwayboard/uploads/directorate/Environment\_Management/2025/pp.pdf

https://www.ndtv.com/india-news/centres-auditor-cag-flags-e-coli-in-drinking-water-across-railway-stations-11915441

https://www.who.int/publications/i/item/9789240121225

https://www.cdc.gov/ecoli/php/technical-info/

https://indianrailways.gov.in/railwayboard/uploads/directorate/Environment\_Management/2025/pp.pdf

https://www.cdc.gov/ecoli/signs-symptoms/index.html

https://www.cdc.gov/ecoli/signs-symptoms/hus.html

https://www.ndtv.com/health/doctor-explains-how-water-quality-impacts-gut-health-immunity-and-long-term-disease-risk-10453746

https://indianrailways.gov.in/railwayboard/uploads/PDF/MX-M464N\_20230628\_143346.pdf

https://www.ndtv.com/health/doctor-explains-how-water-quality-impacts-gut-health-immunity-and-long-term-disease-risk-10453746

Necrotising fasciitis is a rare, and serious bacterial infection that affects the tissue beneath the skin, including the fascia, which surrounds muscles and other structures. It can cause tissue to die quickly, which is why it is sometimes described as a "flesh-eating disease". The term does not mean that bacteria literally eat flesh. Instead, certain bacteria release toxins and trigger an aggressive inflammatory response that damages blood vessels and tissues. Without rapid treatment, the infection can spread through the body and become fatal.

https://www.ndtv.com/health/are-acrylic-nails-doing-irreversible-damage-to-your-health-11448257

https://www.ndtv.com/health/girl-develops-sepsis-after-appendix-bursts-the-severe-complications-of-sepsis-that-you-should-watch-for-11909365

https://www.ndtv.com/health/daveigh-chase-died-of-bacterial-meningitis-complications-at-35-why-stopping-the-infection-in-time-matters-11653414

https://www.ndtv.com/health/rajasthans-medical-mystery-why-are-new-mothers-dying-in-kota-falling-critically-ill-in-bikaner-11633800

https://www.ndtv.com/health/diabetes-and-prediabetes-linked-to-susceptibility-of-severe-infection-study-finds-11608162

https://www.ndtv.com/health/gujarat-chandipura-virus-outbreak-27-deaths-41-confirmed-cases-reported-11911828

Two hormones are key drivers of PMOS: insulin, which acts like a key to let blood sugar into cells, and testosterone, which among other things helps maintain sexual desire, bone density and muscle mass.

Most women with PMOS, regardless of their body size, have insulin resistance, which means this hormone doesn't work as well as it should, said Cree, PMOS clinic director at Children's Hospital Colorado. In many women, the high insulin can go directly to the ovaries, spurring them to make more testosterone and leading to problems like skipped periods, severe acne and even beard growth.

https://www.mayoclinic.org/diseases-conditions/pcos/symptoms-causes/syc-20353439

https://www.thelancet.com/journals/lancet/article/PIIS0140-67362600717-8/fulltext

https://pubmed.ncbi.nlm.nih.gov/42294900/

Population size and genetic diversity respond on different timescales. A population can grow explosively in a few thousand years while carrying variants descended from a far smaller group. New mutations accumulate slowly. Genetic drift, the random loss of variants as generations reproduce, can remove diversity much faster when a population is small.

The 1000 Genomes Project cataloged more than 88 million variants across 2,504 people from 26 populations, which sounds like enormous variation. It is enormous in absolute terms, yet any two human genomes remain overwhelmingly alike. That combination is possible because a genome contains billions of positions. A small percentage difference still amounts to millions of variants, while leaving humans less diverse than several other primate species.

https://www.nature.com/articles/nature15393

https://www.science.org/doi/10.1126/science.abq7487

https://scienceblog.com/early-ancestral-bottleneck-couldve-spelled-the-end-for-modern-humans/

https://pmc.ncbi.nlm.nih.gov/articles/PMC11708913/

https://pmc.ncbi.nlm.nih.gov/articles/PMC11848514/

https://www.nature.com/articles/s41588-025-02323-x

https://academic.oup.com/mbe/article/43/7/msag157/8723835?login=false

A new paper in Science Advances cites an “incomplete” or “insufficient” enzymatic metabolism of the proposed last universal common ancestor (LUCA) as evidence for “independent origins of unrelated enzymes for the same reaction” in two of the basic domains of life, Archaea and Bacteria. The breadth of genomic evidence surveyed in this study is impressive, and their finding is striking because, when properly understood, it strongly contradicts the expectations of universal common ancestry.

The basic idea is that certain enzymes common to all members of Bacteria perform the same basic functions as enzymes in Archaea. However, those enzymes are so fundamentally different (i.e., non-homologous) that they could not be derived from some common ancestor enzyme that was present in LUCA. These enzymes aren’t trivial — they perform fundamental functions in both domains of life. As the paper puts it, they are “required for the synthesis of amino acids, cofactors, and nucleobases.”

https://www.science.org/doi/10.1126/sciadv.aef3128

https://en.wikipedia.org/wiki/Last\_universal\_common\_ancestor

It seems almost backwards when you think about it, a snake can swallow prey whole and strike with lethal venom, yet there's a whole category of birds out there that hunt snakes as a regular part of their diet, sometimes going after cobras and vipers without a second thought. Evolution has handed a surprising number of species the tools to pull this off, thick scales that shrug off fangs, stomach acid strong enough to dissolve venom, or simply the speed and precision to strike first. Here's a look at some of the most capable snake hunters in the bird world, and how they actually manage to win that fight.

https://en.wikipedia.org/wiki/Secretarybird

https://en.wikipedia.org/wiki/Roadrunner

https://en.wikipedia.org/wiki/Peafowl

https://en.wikipedia.org/wiki/Hawk

https://en.wikipedia.org/wiki/Crested\_serpent\_eagle

https://en.wikipedia.org/wiki/Grey\_heron

https://en.wikipedia.org/wiki/Great\_horned\_owl