Editorial Note—Darwin and the origin of life

Bold flights of a speculative mind

Darwin television celebrations begin

It has been known for more than 2000 years that some fish can induce painful, numbing sensations when handled. In the late 1600s, it was discovered that this sensation resulted from the production of strong electrical currents produced by the fish (Kellaway 1946). In On the Origin of Species by Means of Natural Selection (1859), Darwin paid special attention to difficulties with his theory, devoting an entire chapter to the subject. The evolution of electrogenesis was one such area of concern. He noted the difference in structure, innervation, and electrical power of different electric organs (EOs), and the absence of geological evidence for a possible common ancestor between the different taxa exhibiting EOs. He concluded that rather than being homologous structures, the EOs of different fishes should be considered analogous structures that evolved independently. He also raised questions about potential functions for weak EOs. Although electric emissions from weakly electric fish had not yet been discovered, Darwin believed that a functional, weak EO was a necessary step in the evolution of strong EOs. About a century later, the rigorous study of a fish that was found to produce weak electric fields provided answers to such questions (Lissman 1951). Behavioral experiments clearly demonstrated that weak EOs function in electrosensory imaging of the environment (active electrolocation) and communication (Lissman 1958; Lissman and Machin 1958). Since these initial discoveries, there has been a wealth of research into the biology of active electrosensory and electromotor systems.

E ven though darwin had presented in 1859 the basic principles of Darwinism in great detail in Origin of Species , it took another eighty years for biologists to fully accept Darwinism. There were many reasons why there was so much disharmony in evolutionary biology during this long period. Perhaps the main reason was that the very concept of Darwinism continued to change over time. And different Darwinians endorsed different combinations of Darwin's five theories (see chapter 6). In my One Long Argument (1991), I describe nine different usages of the term Darwinism, more or less popular at different periods. Only a chronological treatment can do justice to the history of the concept of Darwinism. Stages in the maturation of Darwinism It is now obvious why there was such disharmony in evolutionary biology for the first eighty years. At the beginning, Darwinism simply meant anticreationism. An evolutionist was labeled a Darwinian as long as he adopted at least the theory that evolutionary change was due to natural causes and not to divine action (Mayr 1991, 1997). You were a Darwinian if you considered science a secular endeavor. Accordingly, opponents of natural selection such as T. H. Huxley and Charles Lyell were called Darwinians. No wonder the term Darwinism had so many meanings in the nineteenth century. 1859–1882 The first years after 1859 were a period of considerable confusion in evolutionary biology. To be sure, two of Darwin's five theories, an evolving world and common descent, were at once almost universally accepted.

A molecular phylogenetic analysis of the Andean genus Tarasa (Malvaceae) and related genera yielded unexpected results regarding generic boundaries, the origins of polyploidy, and the morphological attributes of the polyploid taxa. The polyploid species of Tarasa are particularly unusual because they have life histories and floral morphologies that contradict two traditional polyploid dogmas: they are annuals and have smaller floral features (including pollen) than the diploid species. Typically, polyploids are perennial and larger than their parents. Nuclear (ITS1, 5.8S, and ITS2) and chloroplast (psbA-trnH and trnT-trnL spacers, matK-3′ trnK intron) sequence data were used to reconstruct independent phylogenies to test the monophyly of the genus, determine its sister group(s), and investigate the origin of the polyploid species. Neither the nuclear nor the chloroplast phylogeny supports monophyly of Tarasa as currently circumscribed. The high Andean genus Nototriche, the North/South American disjunct genus Sphaeralcea, and Malacothamnus chilensis are placed within the Tarasa clade. The polyploid species of Tarasa are not monophyletic and thus have been generated multiple times. These findings suggest that the unusual morphological features of the tetraploids are the result of convergent evolution and not shared ancestry.

The history of life is characterised by an increase in biological complexity from simple replicators to multicellular organisms. These major evolutionary transitions have in common that independent entities came together and cooperated and that finally a new entity was formed with a new fitness and a single evolutionary fate. Yet, the stable evolution of cooperation poses a classical Darwinian puzzle: Organisms compete over reproduction and selfish individuals that reap the benefits of the cooperation without paying the costs (cheaters) can invade a population of cooperators and drive the disappearance of cooperation. Social insects have become model organisms to study stable cooperation and how conflict between individuals is resolved. Here, I will first summarise what we have learned from social insect research about the evolution of stable cooperation. Besides little-studied ecological factors that determine the benefits and costs of cooperation, two common mechanisms to prevent the spread of cheaters have been identified: (i) common ancestry and aligned evolutionary interests mainly achieved through relatedness and (ii) enforcement mechanisms that make cheating costly. Then, I will show that similar mechanisms have evolved at other levels of the biological hierarchy that favour cooperation. Thirdly, I will present the multilevel selection approach, which promises to be a useful tool to study evolution at multiple selection levels. I will end by showing how a multilevel selection approach in future research might help to quantify benefits and costs of cooperation, so that insect societies and all major evolutionary transitions alike are being recognised as more than the sum of their components.

The year 2009 marked the 200th anniversary of Charles Darwin’s birth and the 150th anniversary of his most influential publication. Darwin transformed the biological sciences in much the same way that Nicolaus Copernicus, Galileo Galilei, and Isaac Newton, centuries earlier, transformed the physical sciences—by demonstrating that the universe operates according to natural laws that fall within the purview of rational scientific inquiry. In 1543, Copernicus published De Revolutionibus Orbium Celestium (“ On the Revolutions of the Celestial Spheres ”) that challenged conventional wisdom that the Earth was the center of creation and instead promoted the idea that natural laws govern the motion of physical objects in the universe. In 1859, in On the Origin of Species (4), Darwin developed the equally revolutionary concept that a natural but nonrandom process—natural selection—yields biological adaptations that otherwise can give the superficial impression of direct intelligent craftsmanship. Actually, Darwin barely mentioned Homo sapiens in On the Origin of Species, cautiously stating only that “much light will be thrown on the origin of man and his history.” More than a decade later, however, Darwin addressed human evolution at considerable length in The Descent of Man and Selection in Relation to Sex (5) wherein can be found many thoughtful passages, such as, “Man may be excused for feeling some pride at having risen, though not through his own exertions, to the very summit of the organic scale; and the fact of his having thus risen, instead of having been aboriginally placed there, may give him hope for a still higher destiny in the distant future.” Of course, much has been learned about humanity’s evolutionary origins and biological conditions since Darwin’s time, not least from the evidence of paleontology, comparative vertebrate biology, and genomics. An emerging field known as “anthropogeny” (6) seeks to understand the evolutionary origins … [↵][1]1To whom correspondence should be addressed. E-mail: javise{at}uci.edu. [1]: #xref-corresp-1-1

A Universal Struggle for Life? A comparative study of the reception of Darwinism among religious thinkers in the Anglo-Saxon world and in the Middle East in the second half of the 19th century Sacha Aellen How was Darwinism and its potential implications experienced by religious thinkers in the 19th century? What features of the perception of Darwinism were local, depending on specific socio-political situations, and which ones were not? These are the questions I tried to answer in my Master Thesis that I submitted last summer. Let us start with the beginning: what exactly is Darwinism? Mostly contained in two of Charles Darwin's books -The Origins of Species and Descent of Man (1871) -, Darwinism is an evolutionary theory composed of two particularly crucial features. First, living beings all share a common ancestry. Through time, they have developed genetic modifications that created divisions between species but they all have a common origin. Second, the living beings that are...

Some Light on the Mystery of Mysteries

Homology is the similarity between organisms due to common ancestry. Introduced by Richard Owen in 1843 in a paper entitled "Lectures on comparative anatomy and physiology of the invertebrate animals", the concept of homology predates Darwin's "Origin of Species" and has been very influential throughout the history of evolutionary biology. Although homology is the central concept of all comparative biology and provides a logical basis for it, the definition of the term and the criteria of its application remain controversial. Here, I will discuss homology in the context of the hierarchy of biological organization. I will provide insights gained from an exemplary case study in evolutionary developmental biology that indicates the uncoupling of homology at different levels of biological organization. I argue that continuity and hierarchy are separate but equally important issues of homology.

Controversy arises with the passage of time by the development of intellect and critical thoughts on the discovery of the theories of the Earth’s origin from primitive to modern hypotheses. The scientists explore the geological history of the Earth by chronostatigraphy or time based monitoring of rock record through geological time scale. Since the evidence is currently insufficient, scientists will need to make more advancement in the study of the origin and evolution of early life. The primitive unicellular organisms existed in an atmosphere made up of gases like methane and ammonia that was not breathable. Life emerged from non-living stuff more than a billion years after the Earth's formation. The idea that all creatures and people evolved over millions of years from one sort into another is a common one today. Abiogenesis is the complex natural process of the origin of life on the habitable Earth by synthesis in the same geological time scale. On the other hand, biological evolution is the successive inheritance of genetic features favoured by natural selection that gives birth of diversity and variation in molecular structures of the Earth’s habitat. Biological diversity is driven by evolutionary mechanisms that results in origin of new species along with sustainability and susceptibility. Human beings along with all other living beings share common resources and common ancestor through the evolutionary tree.

LesaNPV (Leucoma salicis nucleopolyhedrovirus) is an alphabaculovirus group Ib. Potentially, it can be an eco-friendly agent to control the white satin moth Leucoma salicis population. In this study, we have established the relationship between LesaNPV and other closely related alphabaculoviruses. Environmental samples of late instar of white satin moth collected in Poland infected with baculovirus have been homogenized, polyhedra were purified and subjected to scanning and transmission electron microscopy. Viral DNA was sequenced using the Illumina platform and the whole-genome sequence was established by de novo assembly of paired reads. Genome annotation and phylogenetic analyses were performed with the use of bioinformatics tools. The genome of LesaNPV is 132 549 bp long with 154 ORFs and 54.9% GC content. Whole-genome sequencing revealed deletion of dUTPase as well as ribonucleoside reductases small and large subunits region in LesaNPV genome compared to Dasychira pudibunda nucleopolyhedrovirus (DapuNPV) and Orgyia pseudotsugata multiple nucleopolyhedrovirus (OpMNPV) where this region is complete. Phylogenetic analysis of Baculoviridae family members showed that LesaNPV is less divergent from a common ancestor than closely related species DapuNPV and OpMNPV. This is interesting because their hosts do not occur in the same area. The baculoviruses described in this manuscript are probably isolates of one species and could be assigned to recently denominated species Alphabaculovirus orpseudotsugatae, historically originating from OpMNPV. This finding could have significant implications for the classification and understanding of the phylogeographical spread of baculoviruses.

When Charles Darwin was developing his ideas for On the Origin of Species, the most widely accepted estimates of Earth’s age were those of William Thomson (later Lord Kelvin). Kelvin used calculations involving thermodynamics to argue that Earth is only 20–100 million years old—an age far too brief to accommodate evolution by natural selection. Darwin referred to Thomson’s claim as one of his “sorest troubles,” for Darwin understood that the history of life on Earth ultimately relies on geology. Darwin suspected that Earth was much older than Thomson claimed, but Thomson’s enormous stature as a scientist obliged Darwin to reconcile his claims with Kelvin’s data. To accommodate Kelvin’s timeline, Darwin proposed pangenesis as an explanation of inheritance (i.e., every sperm and egg contained “gemmules thrown off from each different unit throughout the body”). Darwin’s explanation sped evolution while avoiding Lamarck’s quasi-spiritual sources of acquired traits. However, Darwin’s explanation of inheritance was wrong (see discussion in Moore et al. 2009a). The age of Earth remains a divisive topic in the modern evolution–creationism controversy. Whereas mainstream science has long acknowledged that Earth is approximately 4.5 billion years old, a vocal group of citizens and religious activists continue to insist that Earth is less than 10,000 years old. Although most geocentrists and flat-Earth advocates have capitulated to scientific evidence, young-Earth creationists continue to reject scientific evidence in favor of religious dictum to claim that Earth is less than 10,000 years old. These antiscience claims have been surprisingly popular with the public. For example, a Gallup Poll in early 2009 reported that “On Darwin’s [200th] Birthday, Only 4 in 10 Believe in Evolution” (Newport 2009), and Berkman et al. (2008) noted that “16% [of biology teachers] believed that human beings were created by God in their present form at one time within the last 10,000 years.” In another study, 12.5% of students were young-Earth creationists (Rutledge and Warden 2000), as are 10%–14% of biology majors (Moore and Cotner 2009). Answers in Genesis’ (AiG) Creation Museum, along with the $27 million in donations required to build it, attest to the appeal of young-Earth creationism. Indeed, AiG’s income for 2005 exceeded $13 million, and that of the Institute for Creation Research (ICR, another religious organization based on young-Earth creationism) exceeded $7 million. For comparison, the 2005 income of National Center for Science Education—the nation’s leading organization that defends the teaching of evolution in public schools—was

Does a cognate receptor know its own effector?

Evolution and Our Inner Conflict