This figure depicts a generic graphical comparison of polar over dominance and polar under dominance. Differential inheritance is shown in a parent-of-origin type fashion in this case.


PrP Sc  (stained in red) revealed in a photomicrograph of scrapie-infected mouse neuronal cells.


Models of normal (PrP C ) and infectious (PrP Sc ) forms of prion protein on a membrane: polypeptide (turquoise); glycans (red); glycolipid anchors (blue). The core structures are based on NMR spectroscopy (PrP C ) and cryo-electron microscopy (PrP Sc ).


Heterodimer model of prion propagation


Fibril model of prion propagation.


The process of fertilization in the ovum of a mouse


Prophase is the first step of cell division in mitosis. As it occurs after G2 of interphase, DNA has been already replicated when prophase begins. [ 1 ]


Fluorescence microscope  image of two mouse cell nuclei in prophase (scale bar is 5 μm). [ 2 ]


Arabidopsis thaliana  cell in preprophase, prophase and prometaphase. Preprophase band is present along the cell wall from images 1–3, is fading in image 4, and disappears by image 5. [ 1 ]


Repressible Q binary expression system.


Intersectional expression patterns possible using GAL4 and QF binary expression systems.


An example of three possible forward reading frames for a strand of DNA.   AGG·TGA·CAC·CGC·AAG·CCT·TAT·ATT·AGC A ·GGT·GAC·ACC·GCA·AGC·CTT·ATA·TTA ·GC AG ·GTG·ACA·CCG·CAA·GCC·TTA·TAT·TAG· C


An example of a section of DNA translated by a computer in all six possible reading frames. The Open Reading Frames (ORFs) for Gene 1 and 2 are highlighted


The two reading frames used by the human mitochondrial genes  MT-ATP8  and  MT-ATP6 .


Performing reassortment with flu viruses


Steps in DNA synthesis, with RPA shown


The Central Valley in California prevents the two salamander populations from interacting with each other which is an example of habitat isolation. After many generations the two salamander gene pools will become mutated caused by natural selection. The mutation will change the DNA sequence of the two populations enough that the salamander populations can no longer successfully breed between each other making the populations of salamander become classified as different species.


The  flowers  of many species of  Angiosperm  have evolved to attract and reward a single or a few pollinator species (insects, birds, mammals). Their wide diversity of form, colour, fragrance and presence of nectar is, in many cases, the result of  coevolution  with the pollinator species. This dependency on its pollinator species also acts as a reproductive isolation barrier.


In  coral reefs ,  gamete incompatibility  prevents the formation of numerous inter-species hybrids.


Mules  are hybrids with interspecific sterility.


Reproductive isolation can be caused by allopatric speciation. A population of  Drosophila  was divided into sub populations selected to adapt to different food types. After some generations the two sub populations were mixed again. Subsequent matings occurred between individuals belonging to the same adapted group. [ 84 ]


Reverse transcriptase is shown with its finger, palm, and thumb regions. The catalytic  amino acids  of the  RNase H  active site and the  polymerase  active site are shown in ball-and-stick form.


Mechanism of reverse transcription in HIV. Step numbers will not match up.


The molecular structure of  zidovudine  (AZT), a drug used to inhibit reverse transcriptase


Tandem slippage of 2 tRNAs at rous sarcoma virus slippery sequence. After the frameshift, new base pairings are correct at the first and second nucleotides but incorrect at wobble position.  E ,  P , and  A  sites of the ribosome are indicated. Location of growing polypeptide chain is not indicated in image because there is not yet consensus on whether the −1 slip occurs before or after polypeptide is transferred from P-site tRNA to A-site tRNA (in this case from the Asn tRNA to the Leu tRNA). [ 8 ]


+1 frameshift occurs as ribosome and P-site tRNA pause to wait for arrival of rare arginine tRNA. The A-site codon in the new frame pairs to anticodon of more common glycine tRNA, and translation continues. [ 13 ]


This is a graphical representation of the HIV1 frameshift signal. A −1 frameshift in the slippery sequence region results in translation of the  pol  instead of the  gag  protein-coding region, or open reading frame (ORF). Both gag and pol proteins are required for reverse transcriptase, which is essential to HIV1 replication. [ 7 ]


A network of  genotypes  linked by mutations. Each genotype is made up of 3  genes : a, b & c. Each gene can be one of two  alleles . Lines link different phenotypes by  mutation . The  phenotype  is indicated by colour. Genotypes abc, Abc, aBc and abC lie on a  neutral network  since all have the same, dark phenotype. Genotype abc is robust since any single mutation retains the same phenotype. Other genotypes are less robust as mutations change the phenotype (e.g. ABc).


Core eukaryotic  metabolic network . Circles indicate  metabolites  and lines indicate conversions by  enzymes . Many metabolites can be produced via more than one route, therefore the organism is robust to the loss of some metabolic enzymes


Each circle represents a functional gene variant and lines represent point mutations between them. Light grid-regions have low  fitness , dark regions have high fitness. ( a ) White circles have few neutral neighbours, black circles have many. Light grid-regions contain no circles because those sequences have low fitness. ( b ) Within a neutral network, the population is predicted to evolve towards the centre and away from 'fitness cliffs' (dark arrows).


Electron micrograph of the ribonucleoprotein of  mumps virus , which has a herring-bone like structure


Results of a hypothetical replicated artificial selection experiment with three treatments.  At generation 0, the base population of organisms had been randomly sampled to create six lines, two of which would be selectively bred for high values of the trait, two for low values of the trait, and two of which would not experience any intentional selection.  The control lines diverged somewhat by random  genetic drift  and possibly unique  mutations , but, overall, did not change in their average phenotype from the beginning of the experiment.  Both of the high-selected lines reached apparent selection limits around generation 20.  Both of the low-selected reached absolute limits near zero around generation 25.


Protein  sequence space can be represented as a space with n  dimensions , where n is the number of  amino acids  in the protein. Each axis has 20 positions representing the 20 amino acids. There are 400 possible 2 amino acid proteins ( dipeptide ) which can be arranged in a 2D grid. the 8000  tripeptides  can be arranged in a 3D cube. Most proteins are longer than 100 amino acids and so occupy large, multidimensional spaces containing an astronomical number protein sequences.


How  directed evolution  climbs fitness landscapes. Performing multiple rounds of directed evolution is useful not only because a new library of mutants is created in each round, but also because each new library uses better mutants as templates than the previous. The experiment is analogous to climbing a hill on a 'fitness landscape,' where elevation represents the desired property. The goal is to reach the summit, which represents the best achievable mutant. Each round of selection samples mutants on all sides of the starting template (1) and selects the mutant with the highest elevation, thereby climbing the hill. This is repeated until a local summit is reached (2).


How  DNA libraries  generated by  random mutagenesis  sample sequence space. The amino acid substituted into a given position is shown. Each dot or set of connected dots is one member of the library. Error-prone PCR randomly mutates some residues to other amino acids. Alanine scanning replaces each reside of the protein with alanine, one-by-one. Site saturation substitutes each of the 20 possible amino acids (or some subset of them) at a single position, one-by-one.


Experimental cross performed by  Thomas Hunt Morgan , illustrating the X-linked inheritance of  white-eyed  mutation in  fruit flies [ 1 ]


An example pedigree chart of the inheritance of a sex-linked disorder


Three main mechanisms of dosage compensation observed in common model eukaryotic organisms.


Platypus, a type of monotreme


Overview of the use of the SOS response for genotoxicity testing


A current model of meiotic recombination, initiated by a double-strand break or gap, followed by pairing with an homologous chromosome and strand invasion to initiate the recombinational repair process. Repair of the gap can lead to crossover (CO) or non-crossover (NCO) of the flanking regions. CO recombination is thought to occur by the Double Holliday Junction (DHJ) model, illustrated on the right, above. NCO recombinants are thought to occur primarily by the Synthesis Dependent Strand Annealing (SDSA) model, illustrated on the left, above. Most recombination events appear to be the SDSA type.


Arrayed yeast showing synthetic lethal interactions. Synthetic lethal interactions are those pairs of colonies with reduced or no growth.


Replicating yeast colonies during SGA analysis using a pinning robot


Schematic of basic synthetic lethality. Simultaneous mutations in gene pair confer lethality while any other combination of mutations is viable.


A molecular structure composed of unwound and unpaired DNA, where a short stretch of nucleotides are exposed on each strand of the double helix, allowing RNA polymerase binding, and nascent RNA synthesis within this region.


Transcriptional amplification involves increases in global levels of mRNAs produced from expressed genes and may be either uniform across all expressed genes or variable from gene to gene.


This is a Manhattan plot for microcirculation genome associations. On the X-axis it shows genes by chromosome, and on the Y-axis it shows the log of the P-values.


The "triangle of U" diagram, showing the genetic relationships among six species of the genus  Brassica . Chromosomes from each of the genomes A, B and C are represented by different colours.


Images of some of the possible intermediate secondary structures: (A) Intramolecular triplex, (B) Triloop, (C) Tetraloop


Carl Correns


The protein structure of a Universal Stress Protein found in  Haemophylus influenzae   [ 4 ]


This schematic shows a generalised bacterial response to an environmental stress. In this case, it depicts increased levels of Nitric Oxide which stimulates  Usp  gene transcription. This results in an anti-stress response from the cell which may or may not include the responses listed within the diagram. [ 13 ]


Fig 1. Karyotype of human male using  Giemsa  staining


Fig 2. Virtual karyotype of a chronic lymphocytic leukemia sample using a SNP array.


Fig 3. Virtual karyotype log2ratio plot of a chronic lymphocytic leukemia sample using a SNP array. Yellow = copy number of 2 (normal/diploid), aqua = 1 (deletion), pink = 3 (trisomy).


Fig 4. Schematic of a region of a chromosome before and after a duplication event


Fig 5. Her2 Amplification by SNP array virtual karyotype.


Fig 6. Copy neutral LOH/uniparental disomy


Fig 7. Virtual karyotype of a colorectal carcinoma (whole genome view) demonstrating deletions, gains, amplifications, and acquired UPD (copy neutral LOH).


Schematic karyogram of a human, with annotated  bands and sub-bands  as used in the  International System for Human Cytogenomic Nomenclature  for the locations of genetic abnormalities. It shows 22  homologous   autosomal  chromosome pairs, both the female (XX) and male (XY) versions of the two  sex chromosomes , as well as the  mitochondrial genome  (at bottom left).  Further information:  Karyotype


Diagram of  August Weismann 's  germ plasm  theory. The hereditary material, the germ plasm, is confined to the  gonads . Somatic cells (of the body)  develop afresh  in each generation from the germ plasm. Whatever may happen to those cells does not affect the next generation.


X-linked recessive inheritance


Patterns of X-linked recessive inheritance in a royal family


Ribosomal rRNA subunits


Phytohemagglutinin


Historical contribution of donor source groups in European peoples according to Hellenthal et al., (2014). Polish is selected to represent Slavic-speaking donor groups from the Middle Ages that are estimated to make up 97% of the ancestry in Belarusians, 80% in Russians, 55% in Bulgarians, 54% in Hungarians, 48% in Romanians, 46% in Chuvash and 30% in Greeks. [ 1 ]


The approximate frequency and variance distribution of haplogroup I-P37 clusters, ancestral "Dnieper-Carpathian" (DYS448=20) and derived "Balkan" (DYS448=19: represented by a single SNP I-PH908), in Eastern Europe per O.M. Utevska (2017).


Prevailing mtDNA hgs


Network of 29 populations constructed with the Neighbor-net approach from FST distances based on the variation of autosomal SNPs.


Admixture analysis of autosomal SNPs of the Balkan region in a global context on the resolution level of 7 assumed ancestral populations.


A simplified model for recent demographic history of Europeans. The panels indicate a possible demographic scenario consistent with the observed signals.


Medieval gene flow within West Eurasia is shown by lines linking the best-matching donor group to the sources of admixture with recipient clusters (arrowhead). Linecolors represent the regional identity of the donor group, and line thickness represents the proportion of DNA coming from the donor group. Ranges of the dates (point estimates) for events involving sources most similar to selected donor groups are shown.


The Impact of Recent Admixture in West Eurasia.


Estimated ancient DNA admixture. Bulgarian: 52% Neolithic farmer (ENF), 32% Western Hunter Gatherer (WHG), 13% Ancestral North Eurasian (ANE).


Samples from three prehistoric European ancestor groups compared to modern peoples


PCA and Admixture of the Copper Age Potočani individuals with PCA of other Neolithic & Bronze & Iron Age samples compared to present-day Croats, per Novak, Olalde, Ringbauer et al. 2021.


The approximate frequency and variance distribution of haplogroup I-P37 clusters, ancestral "Dnieper-Carpathian" (DYS448=20) and derived "Balkan" (DYS448=19: represented by a single SNP  I-PH908 ), in Eastern Europe per O.M. Utevska (2017).


The distribution of haplogroup  E-V13  in Europe.


The mtDNA haplogroups hypothetical  Out of Africa  migrations in thousand of years  before present .


The median plot of Croats from Croatia on a PCA including European countries, per Gilbert et al. 2022. [ 59 ]


Proposed migration routes (Wang 2013) of dominant East Asian paternal haplogroups (C, D, N, and O), during the peopling of East Asia. [ 2 ]


Proposed migration routes of maternal haplogroups during the peopling of Eurasia. [ 10 ]


A population genomic PCA graph, showing the substructure of Eastern Asian populations. [ 20 ]


Genetic structure of present-day and ancient Eurasians. [ 58 ]


Phylogenetic tree  of Ainu, Ryukyuan, Mainland Japanese, and other Asian ethnic groups. The Ainu and the Ryukyuan were clustered with 100% bootstrap probability, followed by the Mainland Japanese. The three populations in the Japanese Archipelago clustered with the Korean with 100% bootstrap probability. [ 70 ] [ 71 ]


Regional reference panel, PCA, and Admixture analysis.


Estimated ancestry components among modern Eurasian populations. The colored components represent the distinctive genetic markers characteristic of people with red representing East Asian ancestry, Yellow for Siberian ancestry, green for South Asian ancestry, and blue for West Eurasian ancestry. [ 113 ]


A PCA graph illustrates the genetic differences among Han Chinese groups. [ 138 ]


Population structure of Turkic-speaking populations in the context of their geographic neighbors across Eurasia. Turkic-speaking populations are shown in red. The upper barplot shows only Turkic-speaking populations.


Genetic, archeologic and linguistic evidence links the early  Turkic peoples  with Northeast Asian millet-agriculturalists, which later adopted a nomadic lifestyle and expanded from eastern Mongolia westwards.


PCA of various populations in the context of Eurasia and the Americas.


Estimated ancestry components among selected modern populations per Changmai et al. (2022). The yellow component represents East Asian-like ancestry. [ 194 ]


PCA plot of genetic variationof worldwide populations. Australasians (green) cluster relative close to other East Eurasians, such as East/Southeast Asians.


Haplogroup J (Y-DNA) Map on Egypt and the surrounding region. Connecting to the Middle East and Northern Medditeranean.


PCA  plot of 17 contemporary Iberian populations [ 1 ]


(A) Geographic distribution of the inferred proportions in the map. Shadings for proportions are scaled according to the maximum and minimum proportions of each source. (B) Representation of the ADMIXTURE proportions in each target population based on the statistically significant models obtained with qpAdm. [ 22 ]


Distribution of North African Admixture in the Iberian Peninsula


Haplotype-based estimates of genetic sharing between Europe and Africa (Botigué et al. 2013) [ 40 ]


Moura  (literally "Moorish"), a small southern town near the Spanish border, known for its  Moorish heritage


Five component admixture plots for various contemporary Iberian populations against other European, West Asian, North African and West African populations [ 54 ]


Y-DNA haplogroup frequencies in the Iberian Peninsula [ 37 ]


MtDNA haplogroup frequencies in the main Iberian regions [ 77 ]


Distribution of the R1b haplogroup in Europe


Principal Component Analysis of the Italian population [ 1 ]


Timeline summarizing the main demographic events in ancient Italy, from the  Paleolithic  to the  Middle Ages .


Ethnic groups of  Italy  (as defined by today's borders) in the 4th century BC.


Etruscan votive heads, IV-II century BC


Admixture plots of modern West Eurasian populations based on seven components:         South/West European         North/East European         Caucasus         West Asian         South Asian         East Asian         North African/Sub-Saharan African [ 100 ]


The European genetic structure (based on 273,464 SNPs). Three levels of structure as revealed by PC analysis are shown: A) inter-continental; B) intra-continental; and C) inside a single country (Estonia), where median values of the PC1&2 are shown. D) European map illustrating the origin of sample and population size. CEU – Utah residents with ancestry from Northern and Western Europe, CHB – Han Chinese from Beijing, JPT – Japanese from Tokyo, and YRI – Yoruba from Ibadan, Nigeria. [ 35 ]


Glacier cover in Japan at the height of the last glaciation about 20,000 years ago.


Main migration routes into Japan during the Jōmon and Yayoi period.


Phylogenetic tree  of Ainu, Ryukyuan, Mainland Japanese, and other Asian ethnic groups. The Ainu and the Ryukyuan were clustered with 100% bootstrap probability, followed by the Mainland Japanese. The three populations in the Japanese Archipelago clustered with the Korean with 100% bootstrap probability. [ 27 ] [ 28 ]


A population genomic PCA graph, showing the substructure of Eastern Asian populations, including analyzed Japanese Jōmon samples.  Japanese people 's cluster (squares) is almost indistinguishable to the  Korean people 's cluster (circles), while the Jōmon samples are shifted towards the Siberian cluster in a more distinct position. (2020) [ 35 ]


Ancestry profile of Japanese genetic clusters illustrating their genetic similarities to five mainland Asian populations. [ 46 ]


Proposed tripartite styled genomic transitions in parallel with cultural transitions in pre- and protohistoric Japan. (2021)


According to Pietrusewsky, the group most similar to the  Japanese  cranial bones were the  Koreans . Meanwhile,  Chinese ,  Mongolians  and  Southeast Asians  were distinguished from the Japanese. [ 52 ]  (2010)


Principal component analysis  of various populations, including the  Middle East


From right to left: an Egyptian, an Assyrian, a Nubian, and Libyans from the tomb of  Seti I


Arabian Peninsula/East African ancestral components    Levantine ancestral component    Other ancestral components [ 61 ]


Genome-wide  principal component analysis  of world populations with the Levantine cluster shaded in pink [ 61 ]


Multidimensional scaling  analysis of various populations, including Jews and Palestinians [ 71 ]


Y chromosome Haplogroup distribution in Turkey.


Chronological map of the  Austronesian expansion [ 2 ]


The most common Y-DNA Haplogroup type is O, which Filipinos share with Chinese and fellow Southeast Asians. The South Asian Y-DNA H1a indicate the presence of Indians while the 13% frequency of European Y-DNA R1b is evidence of Spanish immigration. [ 9 ] [ 10 ] [ 11 ]


Distribution of Y haplogroup O lineages in East Asia


European genetic structure (based on SNPs) PC analysis


Using the clustering algorithm implemented in ADMIXTURE, ancestral genetic components in Balto-Slavic populations were modeled. [ 5 ]


The people of South Asia are broadly of a mixture of  Western Steppe Herder  (WSH) and native South Asian heritage, the latter of which combines  IVC -related ancestry with  Ancient Ancestral South Indian  (AASI) hunter-gatherer ancestry. [ 1 ]


Y chromosome haplogroup distribution of Turkish people [ 4 ]


Y-DNA comparison of Turkish and Greek-speaking populations of Cyprus, Anatolia, Thrace, the Aegean, and peninsular Greece (Citation: Heraclides et al. 2017 Y-chromosomal analysis of  Greek Cypriots  reveals a primarily common pre-Ottoman paternal ancestry with  Turkish Cypriots . PLoS ONE 12(6): e0179474. doi:10.1371/journal.pone.0179474


Whole genome sequencing of Turkish individuals. [ 1 ]  (b) shows a tree analysis. Turkey, TUR; Tuscans, TSI; Iberian, IBS; British, GBR; Finnish, FIN; European-American, CEU; Northern Han Chinese, CHB; Japanese, JPT; Southern Han Chinese, CHS; Yoruba, YRI; Luhya, LWK. Weight of the migration event predicted to originate from the East Asian branch into Turkey is 0.217; from the ancestral Eurasian branch into the Turkey-Tuscan branch, 0.048; from the African branch into Iberia, 0.026, from the Japanese branch into Finland, 0.079.


Estimated cluster membership bar plot for populations in West Asia, Europe, Africa, South Central Asia, Central Asia, and Siberia. The populations with the largest orange bars, including Turkish people, are located primarily in Southern and Mediterranean Europe, and the northern part of Southwest Asia. [ 8 ]


Population relationships based on fixation index distance estimates. Turks are closest to OCA (Caucasus) and  OME (Iranian and Syrian) groups, compared to other groups or populations such as East-Central European populations (OEC), European (EUR, including Northern and Eastern European), Sardinian, Roma, and Turkmen. [ 9 ]


Helioculture combines brackish water (or  graywater ), nutrients, photosynthetic organisms, carbon dioxide, and sunlight to create fuel.


Founder and CEO Jonathan S. Wolfson


Solazyme Soladiesel shown in the company laboratory.


Aristotle  (384–322 BC) is credited with raising the distinction between personal and logical arguments.   [ 1 ]


Supermarket shelf with four different brands advertising themselves, in some form, as "natural"


Dr. Samuel Johnson. Originator of the appeal to the stone.


Toulmin argumentation framework example.


An Euler diagram illustrating the association fallacy


An attendee at the 2010  Rally to Restore Sanity and/or Fear  wearing a T-shirt implicitly referencing Godwin's Law: "I disagree with you but I'm pretty sure you're not Hitler."


The Roman politician  Marcus Tullius Cicero  coined the phrase  ipse dixit , which translates from the Latin as "he said it himself".


Adolf Hitler  (1889–1945) in 1938


Stolpersteine  of two of the Leiss family in  Moers , punished due to the desertion of Wenzeslaus Leiss.


Himmler in 1945


Rommel in 1942


Key ANNOVAR program workflows


Broad overview of an application of ANNOVAR for identifying mutations for rare disease


Gene Designer clones with a drag and drop feature. Users can drag a  vector  and insert into the Cloning Tool; cut, combine and  clone . Gene Designer assembles a  clone  that can then be dropped directly into a project.


An example of a neighbor-net  phylogenetic network  generated by  SplitsTree  v4.6.


Usage pathway for SnpEff


SnpEff Input File Example


SnpEff Output Example


The approximate frequency and variance distribution of haplogroup I-P37 clusters, ancestral "Dnieper-Carpathian" (DYS448=20) and derived "Balkan" (DYS448=19: represented by a single SNP I-PH908), in Eastern Europe per O.M. Utevska (2017).


The Great Hall,  Oundle School


At the  University of Texas at Austin , March 2008


Dawkins at  Cooper Union  in  New York City  to discuss his book  The Greatest Show on Earth: The Evidence for Evolution  in 2010


Lecturing on his book  The God Delusion , 24 June 2006


Wearing a  scarlet 'A'  lapel pin, at the 34th annual conference of  American Atheists  (2008)


With  Ariane Sherine  at the  Atheist Bus Campaign  launch in London, January 2009


Speaking at  Kepler's Books ,  Menlo Park ,  California , 29 October 2006


Musician  Jayce Lewis  at Dawkins' home in 2018 while working on  Million  (Part 2)


Receiving the  Deschner Prize  in  Frankfurt , 12 October 2007, from  Karlheinz Deschner


Dawkins accepting the Services to Humanism award at the British Humanist Association Annual Conference in 2012


Mendel Lectures' logo with black outline