Lifeboat Foundation

“Interstellar Travel and Post-Humans” by Martin Rees is one of the chapters of the book “The Next Step: Exponential Life”.

Astronomers like myself are professionally engaged in thinking about huge expanses of space and time. We view our home planet in a cosmic context. We wonder whether there is life elsewhere in the cosmos. But, more significantly, we are mindful of the immense future that lies ahead—the post-human future where our remote descendants may transcend human limitations—here on Earth but (more probably) far beyond. This is my theme in the present chapter.

The stupendous timespans of the evolutionary past are now part of common culture. But the even longer time-horizons that stretch ahead—though familiar to every astronomer —have not permeated our culture to the same extent. Our Sun is less than half way through its life. It formed 4.5 billion years ago, but it has got six billion more before the fuel runs out. It will then flare up, engulfing the inner planets and vaporizing any life that might still remain on Earth. But even after the Sun’s demise, the expanding universe will continue—perhaps forever—destined to become ever colder, ever emptier.

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Sediments in which archaeological finds are embedded have long been regarded by most archaeologists as unimportant by-products of excavations. However, in recent years it has been shown that sediments can contain ancient biomolecules, including DNA. “The retrieval of ancient human and faunal DNA from sediments offers exciting new opportunities to investigate the geographical and temporal distribution of ancient humans and other organisms at sites where their skeletal remains are rare or absent,” says Matthias Meyer, senior author of the study and researcher at the Max Planck Institute for Evolutionary Anthropology in Leipzig.

To investigate the origin of DNA in the sediment, Max Planck researchers teamed up with an international group of geoarchaeologists—archaeologists who apply geological techniques to reconstruct the formation of sediment and sites—to study DNA preservation in sediment at a microscopic scale. They used undisturbed blocks of sediment that had been previously removed from archaeological sites and soaked in synthetic plastic-like (polyester) resin. The hardened blocks were taken to the laboratory and sliced in sections for microscopic imaging and genetic analysis.

The researchers successfully extracted DNA from a collection of blocks of sediment prepared as long as 40 years ago, from sites in Africa, Asia, Europe and North America. “The fact that these blocks are an excellent source of ancient DNA—including that originating from hominins—despite often decades of storage in plastic, provides access to a vast untapped repository of genetic information. The study opens up a new era of ancient DNA studies that will revisit samples stored in labs, allowing for analysis of sites that have long since been back-filled, which is especially important given travel restriction and site inaccessibility in a pandemic world,” says Mike Morley from Flinders University in Australia who led some of the geoarchaeological analyses.

A major new study of ancient DNA has traced the movement of people into southern Britain during the Bronze Age. In the largest such analysis published to date, scientists examined the DNA of nearly 800 ancient individuals.

The new study, led by the University of York, Harvard Medical School, and the University of Vienna, shows that people moving into southern Britain around 1300‒800 BC were responsible for around half the genetic ancestry of subsequent populations.

The combined DNA and archaeological evidence suggests that, rather than a violent invasion or a single migratory event, the genetic structure of the population changed through sustained contacts between mainland Britain and Europe over several centuries, such as the movement of traders, intermarriage, and small scale movements of family groups.

Analysis of ancient DNA from one of the best-preserved Neolithic tombs in Britain by a team involving archaeologists from Newcastle University, UK, and geneticists at the University of the Basque Country, University of Vienna and Harvard University, has revealed that most of the people buried there were from five continuous generations of a single extended family. Credit: Newcastle University/Fowler, Olalde et al.

Although the right to use the tomb ran through patrilineal ties, the choice of whether individuals were buried in the north or south chambered area initially depended on the first-generation woman from whom they were descended, suggesting that these first-generation women were socially significant in the memories of this community.

There are also indications that ‘stepsons’ were adopted into the lineage, the researchers say — males whose mother was buried in the tomb but not their biological father, and whose mother had also had children with a male from the patriline. Additionally, the team found no evidence that another eight individuals were biological relatives of those in the family tree, which might further suggest that biological relatedness was not the only criterion for inclusion. However, three of these were women and it is possible that they could have had a partner in the tomb but either did not have any children or had daughters who reached adulthood and left the community so are absent from the tomb.

“Each of these mutations teach us something, and point to a particular gene as a potential target for new and more effective pain medications,” said Dr. Stephen G. Waxman, a neurologist at Yale, told the New York Times.

The hope is that discoveries like these lead to better treatments for chronic pain, which affects about 50 million U.S. adults and is often the reason people become addicted to opioids. Scientists also plan to investigate how Cameron’s wounds seem to heal quickly and leave little scarring.

Researchers have discovered that using a thin-film coating of copper or copper compounds on surfaces could enhance copper’s ability to inactivate or destroy the SARS-CoV-2 virus responsible for COVID-19.

In a study that began soon after the pandemic hit in March 2020, University of Waterloo engineering graduate students investigated how six different thin metal and oxide coatings interacted with HCov-229E, a coronavirus that is genetically like SARS-CoV-2 but safer to work with.

“While there was already some data out there on the lifetime of the virus on common-touch surfaces like stainless steel, plastics and copper, the lifetime of the virus on engineered coatings was less understood,” said Kevin Mussleman, the Waterloo mechanical and mechatronics engineering professor who led the study.

Aging is a highly complex process with thousands of genes influencing our health, which poses a challenge for researchers looking to explain and target the underlying processes that lead to declining health. Researchers from the Babraham Institute’s Epigenetics research program have published a map of genetic interactions in C. elegans in iScience which can be used to identify new genes that influence lifespan and that have equivalent genes in humans.

Researchers use simple model organisms like the nematode worm C. elegans to gather information that can inform studies on human aging because many genes are shared or have counterparts in other species. However, there are some conceptual and technical challenges that apply to the study of aging in model organisms. Dr. Casanueva, Group leader in the Epigenetics research program explains: “The way researchers usually study gene function is by disrupting its function and observing what happens. The disruption of some genes causes worms to live a very long-life. In this way, researchers have found the so-called ‘longevity-pathways.” However, the complexity underlying aging means that it is not enough to focus on individual genes. We need to study the overall organization of longevity by generating a systems-wide view.”

In collaboration with the physicist Marta Sales Pardo at University of Rovira i Virgili, Dr. Casanueva and her lab set out to cast a wider net when it comes to studying longevity genes. Together they created the largest network of gene regulatory interactions that are found in a long-lived type of C. elegans. In this network, the relationships between genes are represented by lines, and represented in different layers based on the flow of information between genes. The middle of the web represents the genes with the most influence, in this case, they receive complex input signals and de-code them, and connect to an output layer of genes. The researchers found that most key genes for longevity belong to transcription factors and metabolic genes.

In 1971, scientists turned to genetics to control disease-spreading mosquitoes without DDT. Today, there are a variety of pesticide-free methods.

Jamie Metzl is an author specializing in topics of genetic engineering, biotechnology, and geopolitics. Please support this podcast by checking out our sponsors:
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