ReThink | Evolved 3 Rar Free Download
Alfonzo Liebenstein
Sharks have skeletons made cartilage, which is around half the density of bone. Cartilaginous skeletons are known to evolve before bony ones, but it was thought that sharks split from other animals on the evolutionary tree before this happened; keeping their cartilaginous skeletons while other fish, and eventually us, went on to evolve bone.
Now, an international team led by Imperial College London, the Natural History Museum and researchers in Mongolia have discovered a fish fossil with a bony skull that is an ancient cousin of both sharks and animals with bony skeletons. This could suggest the ancestors of sharks first evolved bone and then lost it again, rather than keeping their initial cartilaginous state for more than 400 million years.
Most of the early fossils of fish have been uncovered in Europe, Australia and the USA, but in recent years new finds have been made in China and South America. The team decided to dig in Mongolia, where there are rocks of the right age that have not been searched before.
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Charles Darwin conceived of evolution by natural selection without knowing that genes exist. Now mainstream evolutionary theory has come to focus almost exclusively on genetic inheritance and processes that change gene frequencies.
Yet new data pouring out of adjacent fields are starting to undermine this narrow stance. An alternative vision of evolution is beginning to crystallize, in which the processes by which organisms grow and develop are recognized as causes of evolution.
Some of us first met to discuss these advances six years ago. In the time since, as members of an interdisciplinary team, we have worked intensively to develop a broader framework, termed the extended evolutionary synthesis1 (EES), and to flesh out its structure, assumptions and predictions. In essence, this synthesis maintains that important drivers of evolution, ones that cannot be reduced to genes, must be woven into the very fabric of evolutionary theory.
The number of biologists calling for change in how evolution is conceptualized is growing rapidly. Strong support comes from allied disciplines, particularly developmental biology, but also genomics, epigenetics, ecology and social science1,2. We contend that evolutionary biology needs revision if it is to benefit fully from these other disciplines. The data supporting our position gets stronger every day.
Here we articulate the logic of the EES in the hope of taking some heat out of this debate and encouraging open discussion of the fundamental causes of evolutionary change (see Supplementary Information).
SET explains such parallels as convergent evolution: similar environmental conditions select for random genetic variation with equivalent results. This account requires extraordinary coincidence to explain the multiple parallel forms that evolved independently in each lake. A more succinct hypothesis is that developmental bias and natural selection work together4,5. Rather than selection being free to traverse across any physical possibility, it is guided along specific routes opened up by the processes of development5,6.
Mathematical models of evolutionary dynamics that incorporate extra-genetic inheritance make different predictions from those that do not7,8,9. Inclusive models help to explain a wide range of puzzling phenomena, such as the rapid colonization of North America by the house finch, the adaptive potential of invasive plants with low genetic diversity, and how reproductive isolation is established.
Such legacies can even generate macro-evolutionary patterns. For instance, evidence suggests that sponges oxygenated the ocean and by doing so created opportunities for other organisms to live on the seabed10. Accumulating fossil data indicate that inherited modifications of the environment by species has repeatedly facilitated, sometimes after millions of years, the evolution of new species and ecosystems10.
The above insights derive from different fields, but fit together with surprising coherence. They show that variation is not random, that there is more to inheritance than genes, and that there are multiple routes to the fit between organisms and environments. Importantly, they demonstrate that development is a direct cause of why and how adaptation and speciation occur, and of the rates and patterns of evolutionary change.
Researchers in fields from physiology and ecology to anthropology are running up against the limiting assumptions of the standard evolutionary framework without realizing that others are doing the same. We believe that a plurality of perspectives in science encourages development of alternative hypotheses, and stimulates empirical work. No longer a protest movement, the EES is now a credible framework inspiring useful work by bringing diverse researchers under one theoretical roof to effect conceptual change in evolutionary biology.
The evolutionary phenomena championed by Laland and colleagues are already well integrated into evolutionary biology, where they have long provided useful insights. Indeed, all of these concepts date back to Darwin himself, as exemplified by his analysis of the feedback that occurred as earthworms became adapted to their life in soil.
So, none of the phenomena championed by Laland and colleagues are neglected in evolutionary biology. Like all ideas, however, they need to prove their value in the marketplace of rigorous theory, empirical results and critical discussion. The prominence that these four phenomena command in the discourse of contemporary evolutionary theory reflects their proven explanatory power, not a lack of attention.
We see a very different world. We consider ourselves fortunate to live and work in the most exciting, inclusive and progressive period of evolutionary research since the modern synthesis. Far from being stuck in the past, current evolutionary theory is vibrantly creative and rapidly growing in scope. Evolutionary biologists today draw inspiration from fields as diverse as genomics, medicine, ecology, artificial intelligence and robotics. We think Darwin would approve.
We invite Laland and colleagues to join us in a more expansive extension, rather than imagining divisions that do not exist. We appreciate their ideas as an important part of what evolutionary theory might become in the future. We, too, want an extended evolutionary synthesis, but for us, these words are lowercase because this is how our field has always advanced16.
The best way to elevate the prominence of genuinely interesting phenomena such as phenotypic plasticity, inclusive inheritance, niche construction and developmental bias (and many, many others) is to strengthen the evidence for their importance.
A recently published global genome study that used the data-intensive Gordon supercomputer at the San Diego Supercomputer at the University of California, San Diego, has researchers rethinking how avian lineages diverged after the extinction of the dinosaurs.
The genome-scale phylogenetic analysis of the 48 bird species considered approximately 14,000 genes. This presented computational challenges not previously encountered by researchers in smaller-scale phylogenomic studies based on analyses of only a few dozen genes. The inclusion of hundreds of times more genetic data per species allowed the researchers to realize the existence of new inter-avian relationships.
Developed by Alexandros Stamatakis, head of the Scientific Computing Group at HITS, ExaML couples the popular RAxML search algorithm for inference of phylogenetic trees using maximum likelihood with an innovative MPI parallelization approach. This yields improved parallel efficiency, especially on partitioned multi-gene or whole-genome data sets.
Because living apes easily reach eatable fruit in trees with their upright bodies, anthropologists have long thought that this is a primary reason why they evolved over millions of years to have an upright torso. But now new research by an international team of paleontologists suggests that apes ate leaves in forests some 21 million years ago, and this drove their evolution to becoming upright creatures.
James Rossie, associate professor in the Department of Anthropology in the College of Arts and Sciences at Stony Brook University and a member of the international collaboration, and his co-authors describe the finding in a newly published paper in Science, along with a complimentary Science paper highlighting the grassy woodland habitats of the time, which sheds light on the lives of ancient apes, their habits and thus evolution.
New research articulated in these papers provides evidence from the REACHE project that pushes the timeframe back on when apes became upright, and what they ate, forcing scientists to rethink ape evolution.
Scientists involved focused on different aspects of early ape paleoenvironments. The study, led by University of Michigan Professor Laura MacLatchy, revolves around a 21-milliion-year-old ape fossil called Morotopithecus, from Moroto, an upright ape.
MacLatchy and the team examined fossils found in a single stratigraphic layer, including fossils of this oldest ape over that time at Moroto. Within this layer included fossils of other mammals, ancient soil evidence and tiny silica particles from plants. They used this evidence to recreate the environment of Moroto.
Previously, researchers believed equatorial Africa during the Early Miocene was thickly covered in forest, and that woodlands and grasslands emerged 7 to 10 million years ago, but this study suggests it was more like 21 million years ago.
Stony Brook University Hospital (SBUH) has once again been recognized by the U.S. Department of Health and Human Services (HHS) for its public commitments to decarbonizing its operations and improving resilience in the...
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