Tag Archives: evolution
New 90-million-year-old fossil turtle discovered living alongside dinosaurs in the Zuni Basin, NM
A new fossil species of Cretaceous baenid (extinct turtle) was recently discovered from the Moreno Hill Formation in the Zuni Basin of western New Mexico. The new species, known as Edowa zuniensis (Fig. 1), is the first
The SETOC: Visualizing carcinogenesis through a different lens
The Systemic-Evolutionary Theory of the Origin of Cancer (SETOC) is a recently proposed theory based on two fundamental principles: (i) Margulian evolution as a process of cooperation and endosymbiosis and (ii) Systemic cell biology understood as the
Epigenetic phenotype diversification helps animals to adapt to changing and new environments
There is increasing evidence that epigenetic phenotype variation can contribute to environmental adaptation, speciation and evolution. Epigenetic changes of the phenotype are caused by differences in gene expression rather than by alteration of the genetic code. Epigenetic
Forward and reverse mutations in stages of cancer development
Mutations in somatic genomes are known to be the basis of cancers, understanding of which is essential for cancer prevention, diagnosis and therapy. In our study, mutations changing the genomic DNA sequences of a cell from its
Arthropod-specific viruses: where did they come from, what are they doing and where are they going?
Among the hundreds of arthropod-borne viruses (arboviruses), some, for example dengue, West Nile, and yellow fever, cause significant human infections. Millions of infections with symptoms ranging from mild fever to fatal encephalitis occur annually. The suffering is
Evolution and adaptive value of yeast epigenetic memory of previous growth in galactose
Cellular adaptation to environmental changes often entails transcriptional responses that promote survival and proliferation. In certain cases, “memory” of previous experiences promotes a much faster transcriptional response upon second exposure to the same stimuli, leading to faster
Can the chloroplast division machinery be evolutionarily dated back to bacteria?
The chloroplast, known to have originated around a billion years ago, is now one of the most recognizable characteristics of the plant cell. After the engulfment of the ancient cyanobacterium by the eukaryotic host cell, the former
Mitochondrial gene discontinuity that translates into fragmented functional proteins
The majority of protein-coding genes in nuclear genomes are interrupted by spliceosomal introns or, less often, by inteins. These intervening sequences are spliced at the RNA or protein level, respectively, so that intact proteins become reconstituted. In
Many solutions to the same problem – cellular response to environmental challenges
When in contact with a hot object, our immediate response is to withdraw our hand. This instinctive reaction is an example of how external environment shapes our actions. In a similar fashion, bacteria are constantly monitoring and
Coevolutionary games and dynamic fitness landscapes: A synthesis?
A main feature of Darwinian evolution is that success in survival and reproduction is directed by selective pressure and entails competition among individuals. In other words, it is largely justified to recognize the proverbial survival of the
What we know of evolution of the pelvis and walking upright
As children grow, the shape of the spine slowly changes from a C-shape in a newborn into a double-S-shape during adulthood. In the field of medicine, research has shown that the exact shape of this double-S is
New turtle fossils from Uinta Basin represent last documented members of the extensive Baenidae radiation
The baenid turtles were an extinct clade of North American freshwater river turtles with an extensive radiation spanning from the early Cretaceous (125 million years ago) to the middle Eocene (40 million years ago). More than 30
How birds breathe: Did evolution finally get it right?
Flight and the efficiency of the respiratory system Powered (active) flight is a defining lifestyle trait of birds. Showing the exacting evolutionary requirements for flight, powered flight has only ever developed in insects, the extinct pterodactyls, birds
Rain, rain go away, little amoebas want to race
Soil living amoeba Dictyostelium discoideum has been used as a leading model organism for studying eukaryotic cell differentiation and directional cell migration. These functions are interconnected: starved Dictyostelium cells form multicellular aggregates by directional cell migration, and
Migration led to the microevolution of Chinese short fat-tailed Sheep
China has a long history of sheep domestication and rich resources of sheep breeds. Based on tail type, the Chinese domesticated sheep can be divided into five types: short fat-tailed sheep, long fat-tailed sheep, short thin-tailed sheep,
The evolutionarily conserved role of Sp1 in appendage morphogenesis
Despite millions of years of independent evolution, some aspects of vertebrate and arthropod development share striking similarities. For example the appendages of a mouse and of a fly, at the naked eye doesn’t seem to share too
Cornification derived from keratinization through the addition of new epidermal proteins to keratins
Differentiation of epidermal cells in vertebrates takes place by high production of structural proteins termed keratins that belong to cytoskeletal proteins indicated as Intermediate Filaments (α – keratins). The epidermis of vertebrates is a multilayered epithelium that
Molecular mechanism of phenotypic plasticity
Darwinian evolution is considered to be the way that life adapts in every possible environment in Earth. The great evolutionary biologist of the past century Theodosius Dobzansky used to say: “Nothing in Biology Makes Sense Except in
The arms really can give the legs a helping hand in rehabilitation of human walking
The emergence of upright, bipedal walking is a characteristic of human evolution that separate us from our quadrupedal cousins—other animals. The upright walking posture freed our hands so that we could perform skilled tasks like signaling, carrying,
Repelling water and dirt: superhydrophobic biological surfaces and biomimetic innovations
Life evolved over the last 3.5 billion years: a continuous process of mutation and selection – or trial and error. Today we know of some 1.8 million different species – but assessments indicate the existence of over
