Lifeboat Foundation

Domestic cats exhibit abundant variations in tail morphology and serve as an excellent model to study the development and evolution of vertebrate tails. Cats with shortened and kinked tails were first recorded in the Malayan archipelago by Charles Darwin in 1868 and remain quite common today in Southeast and East Asia. To elucidate the genetic basis of short tails in Asian cats, we built a pedigree of 13 cats segregating at the trait with a founder from southern China and performed linkage mapping based on whole genome sequencing data from the pedigree. The short-tailed trait was mapped to a 5.6 Mb region of Chr E1, within which the substitution c. 5T C in the somite segmentation-related gene HES7 was identified as the causal mutation resulting in a missense change (p. V2A). Validation in 245 unrelated cats confirmed the correlation between HES7-c. 5T C and Chinese short-tailed feral cats as well as the Japanese Bobtail breed, indicating a common genetic basis of the two. In addition, some of our sampled kinked-tailed cats could not be explained by either HES7 or the Manx-related T-box, suggesting at least three independent events in the evolution of domestic cats giving rise to short-tailed traits.

The majority of vertebrate species, with the remarkable exceptions of humans and apes, possess a visible tail throughout their lifespans. The animal tail is an important appendage to the torso and plays adaptive roles in locomotion, balance, communication, thermoregulation and even energy storage¹. In vertebrates, tails vary dramatically in color, size, shape and mobility and represent different evolutionary histories, including multiple independent events of shortening or loss of the tail in distinct lineages. Understanding the genetic causes of intraspecific tail length polymorphism would be one essential step toward elucidating the mechanisms underlying the development and evolution of tails. In laboratory mice, genetic studies of axial skeleton development have identified multiple genes and mutations involved in caudal vertebra development that have pleiotropic effects on fertility, somitogenesis, and meiotic recombination, thus shedding light on vertebrate evolution^2,3,4,5.

In 2016, the European Space Agency announced a call for medium-size missions within their Cosmic Vision Program. In layman’s terms, “medium-size” means moderate-cost (less than 550 million euros, or $610 million) and low-risk, and this is achieved by keeping payloads small and by using proven, heritage technology for both spacecraft and payload. Alongside these common-sense conditions is a third and less tangible quality, that the project be scientifically robust. But when comparing excellent cases from vastly different fields, the merits of one scientific mission over another can seem subjective. It’s not enough to lament the dearth of data in said field, or to establish how a project will discover this or that, or even to show exactly how said “groundbreaking technology” will work. ESA wants a mission that will stir up an unprecedented level of excitement, support, and interest within the scientific community. Here is how they attempt to measure a project’s relevance.

“Each member state has a representative in the Science Programme Committee, and it’s their duty to define the content of the program,” said Luigi Colangeli, head of ESA’s Science Coordination Office. “Study groups work with the various proposals to arrive at something that is compatible with the boundary conditions, in this case, of a M-5, or medium-class mission. Right now, we are studying the evolution of the three missions. And then next year we will put together a peer review panel, who will analyze the three candidates and recommend the best selection to our Director of Science.”

Since the call went out four years ago, ESA have been whittling down proposals, from 25 at the beginning to only three now: Envision, Theseus, or SPICA. In February the EnVision conference took place at the National Centre for Space Studies (CNES) in Paris. EnVision is a low-altitude polar orbiter that is meant to perform high-resolution radar mapping, surface composition, and atmospheric studies of Venus. The purpose of the meeting was to call the Venus community to attention, because the clock is ticking. Consortium members, ESA representatives, and interested scientists from all over the world were in attendance.

Nearly every day, new discoveries are pushing the genetics revolution ever-forward. It’s hard to imagine it’s been only a century and a half since Gregor Mendl experimented with his peas, six decades since Watson and Crick identified the double helix, fourteen years since the completion of the human genome project, and five years since scientists began using CRISPR-cas9 for precision gene editing. Today, these tools are being used in ways that will transform agriculture, animal breeding, healthcare, and ultimately human evolution.

Common practices like in vitro fertilization (IVF) and preimplantation embryo selection make human genetic enhancement possible today. But as we learn more and more about what the genome does, we will be able to make increasingly more informed decisions about which embryos to implant in IVF in the near term and how to manipulate pre-implanted embryos in the longer-term. In our world of exponential scientific advancement, the genetic future will arrive far faster than most people currently understand or are prepared for.

Continue reading “Building a Positive Genetic Future for All” »

Circa 2007

New study says that 7% of human genes are evolving rapidly.

Circa 2017

Hunting for meat was a critical step in all animal and human evolution. A key brain-trophic element in meat is vitamin B₃ / nicotinamide. The supply of meat and nicotinamide steadily increased from the Cambrian origin of animal predators ratcheting ever larger brains. This culminated in the 3-million-year evolution of Homo sapiens and our overall demographic success. We view human evolution, recent history, and agricultural and demographic transitions in the light of meat and nicotinamide intake. A biochemical and immunological switch is highlighted that affects fertility in the ‘de novo’ tryptophan-to-kynurenine-nicotinamide ‘immune tolerance’ pathway. Longevity relates to nicotinamide adenine dinucleotide consumer pathways. High meat intake correlates with moderate fertility, high intelligence, good health, and longevity with consequent population stability, whereas low meat/high cereal intake (short of starvation) correlates with high fertility, disease, and population booms and busts. Too high a meat intake and fertility falls below replacement levels. Reducing variances in meat consumption might help stabilise population growth and improve human capital.

Keywords: Meat, nicotinamide, evolution, NAD(H), vitamin B₃, Malthus, fertility, immunological tolerance, longevity.

Continue reading “Meat and Nicotinamide: A Causal Role in Human Evolution, History, and Demographics” »

Life on Earth is dependent on photosynthesizing plants and algae for food, yet land plants did not evolve until about 450 million years ago, Tang said. “The new fossil suggests that green seaweeds were important players in the ocean long before their descendants, land plants, took control,” he said.

These fossils came from an ancient ocean, but there is still a debate about where green algae originated. “Not everyone agrees with us; some scientists think that green plants started in rivers and lakes, and then conquered the ocean and land later,” Xiao said in a statement.

Moreover, green algae isn’t the oldest algae on record. “There is strong fossil evidence that red algae existed over a billion years ago, and we know the red and green algae diverged from a common ancestor,” Gibson told Live Science in an email. “So, although this doesn’t fundamentally change the way I’ll think about the evolution of life, the discovery of this green algal fossil helps fill an important gap and strengthens an emerging timeline for the evolution of early, complex life.”

The rest of the world is interested, too. Africa contains much more genetic diversity than any other continent because humans originated there. This diversity can provide insights into human evolution and common diseases. Yet fewer than 2% of the genomes that have been analysed come from Africans. A dearth of molecular-biology research on the continent also means that people of African descent might not benefit from drugs tailored to unique genetic variations. Infectious-disease surveillance also falls short, meaning that dangerous pathogens could evade detection until an outbreak is too big to contain easily.

Nigeria is poised to become a hub for genetics research, but a few stubborn challenges block the way.

For three years, anthropologist Alan Rogers has attempted to solve an evolutionary puzzle. His research untangles millions of years of human evolution by analyzing DNA strands from ancient human species known as hominins. Like many evolutionary geneticists, Rogers compares hominin genomes looking for genetic patterns such as mutations and shared genes. He develops statistical methods that infer the history of ancient human populations.

In 2017, Rogers led a study which found that two lineages of ancient humans, Neanderthals and Denisovans, separated much earlier than previously thought and proposed a bottleneck population size. It caused some controversy—anthropologists Mafessoni and Prüfer argued that their method for analyzing the DNA produced different results. Rogers agreed, but realized that neither method explained the genetic data very well.

“Both of our methods under discussion were missing something, but what?” asked Rogers, professor of anthropology at the University of Utah.

Life is usefully defined on the basis of process: Any set of entities that participates in the process of evolution by natural selection is alive. But how does evolution by natural selection—and thus life—get started? The answer is far from obvious. Lack of insight haunts origins of life research and plagues understanding of the major evolutionary transitions, including the transition from cells to multicellular life.

In a new paper published in Nature Ecology & Evolution, a team led by Paul Rainey at ESPCI Paris and the Max Planck Institute for Evolutionary Biology provides a solution. Adopting a theoretical approach inspired from earlier and on-going experiments, Rainey and his team show how ecological circumstances can kick-start life, both from the get-go, and also at each of the major evolutionary transitions.

For entities to participate in the process of evolution by natural selection, entities need to be discreet and vary one to another, entities must replicate and offspring must resemble parental types. These basic Darwinian properties (variation, reproduction and heredity) are such fundamental features of life that it is easy to take their existence for granted. But as Black et al point out, Darwinian properties are derived and require evolutionary explanation. In the absence of any manifestation of heritable variance in fitness evolution is governed by chance alone and the road out of randomness difficult to conceive.