The Best Biological Invention of the Year
The progression in biological sciences manifests in diverse forms. Sometimes, it bursts forth from the deployment of an innovative instrument or the conception of a radical theory, abruptly unlocking numerous avenues for research, and inducing a sensation of vertigo. On other occasions, it evolves gradually, through the gradual accumulation of studies, each representing years of meticulous labor, collectively chipping away at prevailing wisdom and unveiling a more robust, superior intellectual framework. Both types of revolution unleash torrents of novel ideas and insights, enhancing our comprehension of life's intricacies.
The preceding year witnessed a profusion of such occurrences. Notably, researchers achieved the cultivation of "embryo models" — lab-fabricated artificial embryos mirroring real ones — progressing to a more advanced developmental stage than ever before. This achievement holds promise for gaining valuable insights into the growth of human fetuses, though ethical debates regarding the status of these models are likely. In the realm of neuroscience, those exploring depression have moved away from the traditional theory guiding much of the research and pharmaceutical treatment for decades.
However, these biological revolutions encompass not only human ingenuity but also biology itself — instances where evolution enables organisms to undertake unprecedented feats. Biologists have recently unearthed numerous instances of such breakthroughs.
Timekeeping, for instance, is an indispensable function for all living entities, from microorganisms awaiting the next cell division to embryos developing limbs and organs to more intricate creatures tracking the passage of day and night. Researchers worldwide have revealed that certain facets of timekeeping are intertwined with cellular metabolism — signifying the mitochondrion as both a generator and a clock. Other temporal aspects are regulated by a molecular ballet, where specialized proteins pirouette before parting ways.
Researchers anticipate groundbreaking discoveries as they delve into the cultivation of primitive, long-lost cells called Asgard archaea. A billion years ago, these cells formed enduring partnerships with mitochondria's ancestors, giving rise to the first complex cells. The secrets behind this biological breakthrough may be concealed within these exotic cell cultures. Simultaneously, scientists scrutinize the "grit crust" microbes in Chile's arid Atacama Desert, seeking insights into how the initial land-dwelling cells survived.
The year 2023 unveiled a plethora of remarkable biological innovations: plankton enhancing photosynthetic abilities by repurposing one of their membranes, and subterranean microbes mastering oxygen production in complete darkness. An immunological mechanism shielding infants in the womb, and a neurological technique enabling the brain to map social relationships akin to physical landscapes. A minor mutation transforming ants into complex social parasites almost overnight, and a strategic alteration of DNA that worms employ to safeguard their genomes.
Quanta documented these and more throughout the year, promising to remain vigilant for future breakthroughs in fundamental biology. Pushing the Boundaries of Synthetic Life
In the manner that physical scientists construct simple model systems as stepping stones to comprehend more complex phenomena, some biologists prefer understanding life by devising simpler versions. This year, progress was evident on two fronts: on a grand scale, in the creation of "embryo models," and on a smaller scale, in the scrutiny of the most minimal cell conceivable.
Embryo models, or synthetic embryos, emerge as laboratory products from stem cells, induced to progress faithfully through early developmental stages, terminating before replicating the complete embryonic process. These were conceived as potential tools for ethically experimenting with human development. In the current year, research cohorts in Israel and the United Kingdom showcased the ability to nurture embryo models up to (and potentially beyond) the stage allowed for live human embryo research. Chinese researchers even briefly initiated pregnancies in monkeys using embryo models. These triumphs signify significant advancements in a technique that could elucidate crucial aspects of prenatal development, potentially preventing miscarriages and birth defects. Simultaneously, these experiments reignite ethical debates as the more developed embryo models may appear intrinsically deserving of protection.
Synthetic life isn't always ethically contentious. This year, researchers explored the limits of "minimal" cells, uncomplicated organisms derived from bacteria stripped down to their genomic essentials. These minimal cells retain the ability to reproduce, with non-essential genes removed. In a crucial validation of their natural lifelikeness, researchers found that the minimal genome could evolve and adapt. After 300 days of growth and natural selection in the laboratory, these minimal cells could effectively compete against their ancestral bacteria. The findings underscore the resilience of life's fundamental rules — even with almost every genetic resource stripped away, minimal cells employ natural selection tools to reemerge as more successful life forms. The Exploration of Consciousness
Consciousness is the perception of being — an awareness of possessing a unique self, a representation of reality, and a position in the world. Traditionally a domain of philosophers, scientists have made strides in understanding its neurobiological underpinnings.
In a May interview on the Joy of Why podcast, Anil Seth, a neuroscience researcher at the University of Sussex, characterized consciousness as a form of "controlled hallucination." Our reality, he argued, emerges from within us, making it impossible to directly apprehend the world. Every organism, indeed every individual, experiences the world differently. Reality is shaped by sensory information and the brain's organization and construction within consciousness. In this context, our entire experience constitutes a controlled hallucination