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Most recent common ancestor

The most recent common ancestor (MRCA) of a set of organisms, also known as the last common ancestor (LCA), is the most recent individual from which all members of that set are descended through their evolutionary lineages.^[1]^[2] This concept is central to evolutionary biology, as it defines the point of divergence for related taxa and underpins the construction of phylogenetic trees, where the MRCA is represented by the node at which lineages from the group converge.^[3]^[1] In phylogenetics, the MRCA helps quantify relatedness: taxa sharing a more recent MRCA are more closely related than those whose lineages split earlier.^[1] For example, on a phylogenetic tree of mammals, the MRCA of humans and chimpanzees is a hominid ancestor from approximately 6–7 million years ago, while the MRCA of all primates dates back further to around 60–80 million years.^[3] In population genetics, the coalescent theory models the time to the MRCA for gene lineages within a population, often tracing back rapidly due to genetic drift, with the expected time to coalescence for a sample of size n approximating 2N(1 - 1/n) generations in a Wright-Fisher model, where N is the effective population size.^[2] Notable examples illustrate the MRCA's application across scales. The matrilineal MRCA of all living humans, termed "Mitochondrial Eve," is estimated to have lived in Africa between 100,000 and 200,000 years ago, based on mitochondrial DNA variation.^[2] Similarly, the patrilineal MRCA, or "Y-chromosomal Adam," dates to around 200,000–300,000 years ago.^[2] At the broadest level, the Last Universal Common Ancestor (LUCA) is the MRCA of all cellular life on Earth, hypothesized to have been a prokaryote-like organism existing approximately 4.2 billion years ago, with a complex cellular structure including membranes and metabolic pathways.^[4]^[5] These MRCAs do not imply a single founding population but rather the latest point where ancestry coalesces for the specified lineage or group.^[2]

Definition and Concepts

Basic Definition

The most recent common ancestor (MRCA) of a set of organisms, such as species or individuals, is defined as the latest individual from which all members of that set descend through an unbroken lineage of parent-offspring relationships.^[6]^[7] This concept applies broadly in evolutionary biology to genes, populations, or taxa, where the MRCA represents the point of lineage coalescence most proximal to the present.^[2] In the framework of descent with modification, the MRCA embodies the shared heritage among descendants, marking the most recent juncture at which their evolutionary paths diverged while retaining common genetic or phenotypic traits derived from that ancestor.^[6] All descendants inherit elements from this ancestor, but earlier common ancestors exist further back in time, emphasizing that the MRCA is specifically the chronologically latest such shared forebear.^[7] To illustrate, consider a human family tree: the MRCA of two first cousins is typically a shared grandparent, from whom both lineages descend directly without further branching convergence, whereas a great-grandparent serves as a common ancestor but is not the most recent one.^[8]

Distinction from Other Ancestors

The most recent common ancestor (MRCA) is frequently compared to the last common ancestor (LCA), with the two terms often employed interchangeably in phylogenetic analyses to denote the shared progenitor of a group of taxa. However, subtle distinctions arise in usage: the MRCA emphasizes the recency of the shared ancestor for a specific subset of lineages, marking the point of their most recent convergence, whereas the LCA can specifically refer to the basal ancestor at the root of a phylogenetic tree or clade, encompassing all descendants from that divergence event. This differentiation helps clarify relationships within nested clades, where an MRCA for sister taxa may be more recent than the LCA of the broader group.^[9] The MRCA should not be confused with the "first" or original ancestor of a lineage, as it does not represent the earliest evolutionary origin but rather the latest temporal point where descendant lineages unite before diverging. This conceptual focus on recency avoids implying a singular starting point for all evolution, instead highlighting bifurcation events in lineage histories. For instance, on a phylogenetic tree, the MRCA of two terminal taxa is the internal node closest to the present that connects them, distinct from deeper ancestral nodes that might qualify as earlier common ancestors.^[6] A prevalent misconception portrays the MRCA as invariably a single individual, yet in population-level contexts, it often comprises a contemporaneous group of individuals whose collective descendants include all members of the studied set. Mathematical models of ancestry demonstrate that, in expanding populations like that of modern humans, the MRCA can span multiple individuals within one or more generations, rather than pinpointing one person as the sole progenitor. This population-based view aligns with demographic realities, where ancestry coalesces through overlapping contributions rather than linear descent from a lone figure.^[2] In gene trees, the MRCA applies specifically to the coalescence of particular alleles or gene copies sampled from individuals, rather than the entire genome or species history, which can result in topologies that deviate from the species tree due to processes like incomplete lineage sorting. For a given locus, the MRCA traces the most recent union of those allelic lineages, providing insights into localized evolutionary histories without assuming uniformity across the genome. This allele-specific nature underscores the modular structure of genetic inheritance, where different genomic regions may have distinct MRCAs.^[10]

MRCA in Phylogenetics

MRCA of Species

The most recent common ancestor (MRCA) of two or more species is the last population or individual from which their distinct evolutionary lineages diverged, represented as the internal node in a phylogenetic tree where the branches split. This node signifies the point of speciation, after which the descendant lineages evolve independently, accumulating genetic and morphological differences that define separate species. In evolutionary biology, identifying the MRCA of species is fundamental to reconstructing the branching patterns of life's history, as it delineates the boundaries between monophyletic groups. A prominent example is the MRCA of humans (Homo sapiens) and chimpanzees (Pan troglodytes), estimated to have lived between 5 and 7 million years ago based on molecular clock analyses and fossil correlations. Fossil evidence supporting this timeframe includes Sahelanthropus tchadensis, a 7-million-year-old hominid from Chad whose cranial features—such as a small brain size similar to chimpanzees and a more anteriorly positioned foramen magnum suggesting possible bipedalism—indicate it may represent a form close to the human-chimpanzee split. This ancestor likely inhabited forested environments in central Africa, bridging ape-like and early human traits. The MRCA concept is essential for classifying clades, which are monophyletic assemblages comprising the MRCA and all its descendants, thereby organizing biodiversity into hierarchical units like genera, families, and orders. By anchoring phylogenetic trees, MRCAs enable the dating of speciation events through fossil-calibrated molecular phylogenies, providing temporal frameworks for understanding adaptive radiations and extinction patterns. For instance, the MRCA of all extant mammals is estimated at approximately 180 million years ago during the Early Jurassic, derived from genomic reconstructions across diverse mammal orders that align with fossil records of early mammaliaforms.

MRCA within Populations

The most recent common ancestor (MRCA) within a population refers to the most recent individual from whom all members of a defined group—such as a local population, subspecies, or ethnic cohort—descend through genetic inheritance. Unlike broader phylogenetic contexts, this concept focuses on intra-species dynamics, where the MRCA represents the point of coalescence for lineages within a single breeding or geographic unit, often influenced by localized evolutionary processes. A representative example is the MRCA of all modern Europeans, estimated to have lived approximately 1,000 years ago, due to extensive historical intermixing and migration across the continent, as inferred from genetic models of shared recent ancestry. This recency highlights how interconnected European populations have become through centuries of movement and admixture, forming the basis of contemporary genetic diversity.^[11] The recency of a population's MRCA is profoundly shaped by demographic factors. Larger effective population sizes (Ne) extend the expected time to MRCA (TMRCA), as the coalescence rate slows proportionally to 1/(2Ne), leading to older shared ancestors in stable, sizable groups; for instance, in coalescent models, the expected TMRCA for a sample of two individuals is 4Ne generations. Conversely, migration enhances gene flow between subgroups, effectively increasing Ne and delaying coalescence, which can push the MRCA further into the past by incorporating diverse lineages. Bottlenecks, however, drastically reduce Ne temporarily, accelerating coalescence and rendering the MRCA more recent, as lineages merge rapidly during periods of low population numbers, such as during glacial maxima or plagues.^[12]^[13]^[14] In expanding populations, the MRCA often proves surprisingly recent due to founder effects, where small vanguard groups establish new territories, concentrating ancestry in a limited set of individuals whose lineages then radiate outward, minimizing deep coalescence through serial bottlenecks at expansion fronts. This dynamic is evident in models of human dispersal, where rapid growth from modest founding cohorts compresses genealogical timelines, contrasting with the deeper splits seen in isolated or contracting populations.^[11]

Genetic Lineages

Patrilineal MRCA

The patrilineal most recent common ancestor (MRCA), commonly known as Y-chromosomal Adam, is the most recent individual male from whom all living males inherit their Y chromosome through direct paternal descent, representing the coalescence of all extant Y-chromosome lineages.^[15] This concept traces unbroken male-line inheritance, excluding females who do not carry a Y chromosome.^[15] Early genetic studies estimated Y-chromosomal Adam's lifespan at 60,000 to 140,000 years ago, based on initial Y-chromosome sequencing and phylogenetic modeling. Subsequent refinements, incorporating larger datasets and advanced sequencing, pushed this back; a 2023 analysis of 43 diverse human Y chromosomes dated the TMRCA to approximately 183,000 years ago (95% highest posterior density interval: 160,000–209,000 years), with a 2025 study refining this to about 187,000 years ago (173,000–203,000 years) based on an ancestral-like Y reference sequence; evidence from deep-rooted African lineages confirms an origin in Africa.^[15]^[16] The Y chromosome's largely non-recombining structure—spanning the male-specific region (MSY) of about 23 million base pairs, with recombination limited to small pseudoautosomal boundaries—preserves paternal lineages intact across generations, facilitating straightforward phylogenetic tracing.^[15] Single nucleotide polymorphisms (SNPs) in this region accumulate steadily, with an estimated germline mutation rate of roughly 3 × 10^{-8} per base pair per generation (assuming ~30 years per generation), enabling reliable dating of lineages through accumulated variants.^[15] In genetic genealogy, this translates to an effective rate of about one phylogenetically informative SNP every 100–150 years along the Y-chromosome tree. Importantly, Y-chromosomal Adam was not the sole progenitor of modern humans; descent from him occurs only via the patrilineal line, and he coexisted with numerous other males whose lineages have since gone extinct.^[15] For context, this timeline now aligns more closely with that of the matrilineal MRCA (Mitochondrial Eve), estimated at 150,000–200,000 years ago, though the two ancestors were not contemporaries and represent separate uniparental inheritance paths.^[15]

Matrilineal MRCA

The matrilineal most recent common ancestor (MRCA), often referred to as Mitochondrial Eve, is the most recent woman from whom all living humans inherit their mitochondrial DNA (mtDNA) through an unbroken maternal line.^[17] This uniparental inheritance pattern traces back to a single female ancestor in Africa, whose mtDNA lineage coalesced due to the non-recombining nature of mtDNA, which is passed exclusively from mother to all offspring without contribution from the father.^[18] Unlike nuclear DNA, mtDNA evolves rapidly, with a mutation rate approximately 5–10 times higher than nuclear DNA, accumulating about one substitution every 3,500–3,600 years across the entire 16,569-base-pair genome.^[18] This high mutation rate makes mtDNA a valuable tool for studying uniparental inheritance and maternal lineages in human population genetics.^[18] Initial estimates placed Mitochondrial Eve's lifetime at approximately 200,000 years ago, based on mtDNA sequence variation from global populations.^[17] Subsequent refinements using ancient DNA for molecular clock calibration have narrowed and adjusted this to around 150,000–200,000 years ago, with a 2013 study estimating 157,000 years ago (95% highest posterior density interval: 120,000–197,000 years) via sequences from 10 ancient modern humans spanning 40,000 years.^[19] Analyses up to 2023, incorporating larger ancient DNA datasets, continue to support a coalescence time of about 200,000 years ago, confirming her African origin during the emergence of anatomically modern humans.^[20] These estimates derive from phylogenetic analyses of complete mtDNA genomes, calibrated against radiocarbon-dated ancient samples to account for purifying selection and varying substitution rates.^[21] Importantly, Mitochondrial Eve was not the only woman alive at her time, nor the first modern human; thousands of contemporaries existed, but all other maternal mtDNA lineages eventually went extinct through genetic drift, leaving only hers in the present-day population.^[22] Genetic drift, the random fluctuation of allele frequencies in finite populations, favored the persistence of her lineage over millennia, particularly during population bottlenecks and expansions in Africa.^[22] The timeline for the matrilineal MRCA overlaps potentially with that of the patrilineal MRCA (Y-chromosomal Adam), estimated at approximately 180,000–190,000 years ago (160,000–210,000 years), though the two ancestors were not contemporaries and represent separate uniparental histories.^[21]

Estimation Methods

Using Genetic Markers

Genetic markers such as single nucleotide polymorphisms (SNPs), short tandem repeats (STRs), and whole-genome sequencing data are essential for tracing lineages and estimating the most recent common ancestor (MRCA) by identifying shared variations that indicate coalescence events in evolutionary history.^[23] SNPs, which are single base-pair changes, provide stable markers for deep-time ancestry due to their low mutation rates, allowing reconstruction of phylogenetic trees and haplogroup assignments that pinpoint MRCA points.^[24] In contrast, STRs, consisting of repeating DNA segments, mutate more rapidly and are particularly useful for resolving recent genealogical relationships within the last few hundred to thousand years.^[25]^[26] Whole-genome sequencing enhances resolution by capturing millions of SNPs across the genome, enabling finer detection of distant kinship and lineage divergence compared to targeted marker approaches.^[27] The process begins with sequencing DNA from relevant chromosomes, such as the Y-chromosome for patrilineal lines or mitochondrial DNA (mtDNA) for matrilineal lines, followed by alignment to reference genomes to detect variants like SNPs that signal coalescence points where lineages merge.^[28] These variants are then compared across individuals to construct haplotype networks or phylogenetic trees, estimating the MRCA by counting shared mutations and applying mutation rate models.^[29] In human genetics, haplogroup assignment exemplifies this: for instance, identifying specific SNPs on the Y-chromosome, such as those defining haplogroup R1b, groups individuals sharing a common patrilineal ancestor and refines MRCA dating through shared haplotype blocks.^[30] This method applies similarly to mtDNA haplogroups like H, tracing maternal coalescence via non-recombining sequences.^[31] Key tools and databases facilitate marker analysis and lineage tracing. The 1000 Genomes Project provides a comprehensive catalog of human genetic variation, including SNP data from diverse populations, supporting alignment and coalescence inference for global ancestry studies.^[32] For Y-chromosome analysis, FamilyTreeDNA's Big Y test sequences over 100 million base pairs to discover novel SNPs, building a public haplotree that estimates patrilineal MRCAs through shared private variants.^[33] mtDNA databases like MitoSearch and PhyloTree enable haplotype matching for maternal lines by compiling global sequences, allowing users to identify shared mutations and potential MRCAs in non-recombining mtDNA. These resources integrate user-submitted data with reference panels for robust comparisons. Recent advances from 2023 to 2025 in ancient DNA (aDNA) integration have refined marker-based MRCA estimates by calibrating mutation rates and coalescence models with radiocarbon-dated genomes, improving accuracy for both modern and archaic human lineages. For example, aDNA from Neolithic and medieval samples has been used to validate SNP and mtDNA phylogenies, reducing uncertainties in TMRCA predictions by anchoring genetic clocks to fossil records.^[34] This calibration enhances the reliability of tools like whole-genome SNP analysis for tracing population-specific MRCAs.^[35]

Mathematical Models

Coalescent theory provides a foundational mathematical framework for modeling the time to the most recent common ancestor (TMRCA) by tracing lineages backward in time through a population's genealogy. In Kingman's coalescent model, introduced in 1982, the process is approximated as a continuous-time Markov chain where pairs of lineages coalesce at a rate proportional to the inverse of the effective population size, assuming a large, randomly mating population with no selection or migration.^[36] This model simplifies the complex genealogy of a sample of genes, focusing on the stochastic merging of ancestral lineages until they unite at the MRCA. For a sample of two genes in a diploid population of constant effective size N_e, the expected TMRCA, denoted E[T_2], is $2N_e generations.^[37] The derivation begins with the probability that two lineages coalesce in any given generation, which is approximately $1/(2N_e) under the Wright-Fisher model, as this represents the chance that they share a common parent. The waiting time to coalescence follows a geometric distribution with success probability $1/(2N_e), yielding an expected value of $2N_e generations; more generally, for k lineages, the coalescence rate is \binom{k}{2}/(2N_e), and the expected time scales linearly with population size, emphasizing how larger populations lead to longer TMRCA due to reduced coalescence probabilities.^[38] Extensions to Kingman's basic model address real-world complexities, such as population structure. The structured coalescent incorporates spatial or demographic subdivision, where lineages in different demes coalesce within their group but migrate between them, altering coalescence rates based on migration rates and deme sizes; for instance, Hudson's formulation in 1990 models this as a multi-type coalescent process. Population bottlenecks, modeled as sudden reductions in N_e, accelerate coalescence by increasing the probability of lineage merging during the low-size period, thereby shortening the overall TMRCA compared to constant-size scenarios.^[39] These models predict that TMRCA is shorter in small or bottlenecked populations, where heightened coalescence rates compress genealogical depth, a pattern observed theoretically and applied to conservation genetics of endangered species with reduced effective sizes.^[40]

Time to MRCA Examples

TMRCA for All Living Humans

The most recent common ancestor (TMRCA) of all living humans can be examined through both genetic and genealogical lenses. The genetic TMRCA refers to the point at which the lineages of specific genetic markers in all modern humans coalesce, while the genealogical TMRCA identifies the most recent individual from whom every living person descends through any combination of ancestral lines. These concepts highlight how human ancestry converges more recently than might be expected given our species' age of approximately 300,000 years. For genetic markers, mitochondrial DNA (mtDNA), inherited solely from the mother, traces to a TMRCA known as Mitochondrial Eve, estimated at 155,000–160,000 years ago based on 2023 analyses of global mtDNA variation showing an African origin.^[41] Similarly, the Y-chromosome, passed from father to son, points to a Y-chromosomal Adam with a TMRCA around 200,000–300,000 years ago, derived from 2023 sequencing of diverse worldwide Y-chromosomes that reveal punctuated demographic expansions.^[42] In contrast, for autosomal DNA—the bulk of the nuclear genome inherited from both parents—coalescence times vary across loci due to recombination, typically ranging from 100,000 to over 1 million years ago. The genealogical TMRCA, representing the last individual ancestor of all humans regardless of genetic contribution, is estimated at 2,000–3,000 years ago according to computational models incorporating population substructure, migration, and growth rates.^[43] This surprisingly recent date arises from global interconnectivity: even isolated populations eventually share ancestors through intermarriage, compressing the pedigree backward in time. Recent demographic simulations continue to support these estimates without major revisions through 2025. Key factors influencing these TMRCA estimates include the Out-of-Africa migration event around 60,000–70,000 years ago, which created a severe population bottleneck that reduced genetic diversity outside Africa and shaped subsequent coalescent patterns.^[44] Exponential population growth and widespread human migrations have further shortened the genealogical TMRCA by rapidly mixing lineages worldwide. Ancient DNA analyses from 2023 affirm an African origin for modern humans while revealing Eurasian back-migrations into Northeast Africa starting around 5,000–3,000 years ago, introducing up to 40% non-African ancestry in some groups and underscoring the dynamic gene flow that influences both genetic and genealogical convergence.^[45]

Last Universal Common Ancestor

The Last Universal Common Ancestor (LUCA) represents the most recent common ancestor of all extant life on Earth, hypothesized as a prokaryotic population from which the domains Bacteria and Archaea diverged, while eukaryotes emerged later through endosymbiotic events.^[5] LUCA is not considered eukaryotic but rather a complex, single-celled microbe adapted to extreme early Earth conditions. A 2024 study using Bayesian molecular clock methods, calibrated against geological and isotopic evidence, estimates LUCA's existence at approximately 4.2 billion years ago, with a 95% confidence interval of 4.0–4.3 billion years ago.^[5] This timeline pushes LUCA closer to Earth's formation around 4.5 billion years ago than earlier models, which placed it at 3.5–3.8 billion years ago based on less refined phylogenetic dating and fossil correlations.^[5] The revision stems from improved handling of substitution rate variations and incorporation of Hadean-era environmental data.^[5] LUCA's reconstructed genome spanned roughly 2.6 million base pairs, encoding about 2,600 proteins dedicated to core processes like nucleotide synthesis, translation, and energy metabolism via an anaerobic Wood–Ljungdahl pathway.^[5] It inhabited a thermophilic, anaerobic niche near deep-sea hydrothermal vents, relying on hydrogen and carbon dioxide as energy sources in a reducing atmosphere.^[5] Phylogenetic reconstruction identifies 399 conserved protein families as likely present in LUCA, supporting its autotrophic lifestyle and resistance to environmental stresses.^[5] Widespread horizontal gene transfer in early microbial communities further obscures LUCA's vertical inheritance, as genes could have been exchanged across lineages, necessitating rigorous tests to confirm ancestral origins over lateral acquisitions. Recent analyses from 2023 to 2025 reinforce these core genes while highlighting LUCA's role in an interconnected primordial ecosystem.

Advanced Topics

Identical Ancestors Point

The identical ancestors point (IAP), also known as the genetic isopoint, represents the most recent time depth in a population's history at which every individual from that era is either a genealogical ancestor of all living members of the population or an ancestor of none, due to the effects of pedigree collapse where ancestral lines increasingly overlap.^[46] This point lies beyond the most recent common ancestor (MRCA) and marks a transition where the collective pedigree of the present population converges to a universal set of forebears, with no partial contributions from individuals outside that set.^[46] The mathematical basis for the IAP arises in expanding populations, where the expected number of genealogical ancestors doubles each generation backward in time, leading to exponential growth that quickly exceeds the historical population size and forces overlaps through pedigree collapse.^[46] Simulations accounting for factors such as migration, population bottlenecks, and varying growth rates demonstrate that the IAP emerges when these overlapping lineages fill all ancestral slots, resulting in a binary outcome for past individuals: universal ancestry or complete lineage extinction in the present.^[46] For humans, the IAP is estimated to have occurred between approximately 5,300 and 2,200 BCE, based on computational models of global population dynamics.^[46] Recent analyses incorporating identity-by-descent (IBD) tracking, which measures shared DNA segments inherited from common ancestors, have refined these estimates by simulating ancestry propagation in structured populations, confirming the IAP's position several thousand years ago while highlighting its sensitivity to historical migration patterns.^[47] This concept underscores the profound genealogical interconnectedness of all living humans, revealing that despite geographic and cultural separations, our shared ancestry converges rapidly in the relatively recent past, emphasizing the unity of the human family tree.^[46]

Genealogical vs. Genetic MRCA

The genealogical most recent common ancestor (MRCA) refers to the most recent individual from whom an entire group of descendants is linked through all possible ancestral lines in a complete pedigree, representing a holistic connection across the full family tree.^[48] This concept requires tracing every lineage without breaks, making it challenging to reconstruct empirically due to incomplete historical records, though mathematical models demonstrate that such an MRCA can exist relatively recently in large populations.^[48] In contrast, the genetic MRCA pertains to the most recent individual who contributed a specific allele or genetic segment to all members of the group at a particular locus, such as a mitochondrial DNA (mtDNA) haplotype or a Y-chromosome marker.^[49] For uniparentally inherited markers like mtDNA, which do not undergo recombination, the genetic MRCA—often termed "Mitochondrial Eve" for humans—traces unbroken maternal lineages, providing a precise but partial view of ancestry limited to that single genetic pathway.^[49] Autosomal genetic MRCAs, however, are influenced by recombination, which shuffles genetic material during meiosis, resulting in fragmented inheritance where adjacent DNA segments may derive from different ancestors.^[50] The primary distinction lies in scope and traceability: the genealogical MRCA encompasses the entire pedigree and is holistic yet elusive without exhaustive records, whereas the genetic MRCA is locus-specific, offering high precision for targeted genes but capturing only a fraction of overall ancestry. Recombination further accentuates this gap for autosomal DNA, as it breaks chromosomes into segments with independent coalescent histories, meaning a single chromosome can have multiple genetic MRCAs rather than a unified one. This fragmentation implies that while a genealogical MRCA may connect all descendants broadly, their genetic contribution dilutes over generations, potentially leaving no direct DNA traces in modern individuals despite the pedigree link. Recent ancient DNA studies have illuminated these dynamics through evidence of mosaic ancestry, where individual genomes exhibit patchwork contributions from diverse sources, underscoring multiple genetic MRCAs per chromosome in admixed populations.^[53] For instance, analyses of prehistoric East Asian samples reveal complex admixture patterns, with autosomal regions sourcing from varied ancestral components, challenging simplistic single-MRCA models and highlighting how recombination integrates multiple lineages into contemporary genetic profiles.^[53] These findings update understandings of human history by demonstrating that genetic ancestry is not monolithic but segmented, with implications for interpreting admixture events in evolutionary contexts.^[53]

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[40]
Punctuated bursts in human male demography inferred from 1244 ...
We report the sequences of 1244 human Y chromosomes randomly ascertained from 26 worldwide populations by the 1000 Genomes Project.
[41]
Modelling the recent common ancestry of all living humans - PubMed
These analyses suggest that the genealogies of all living humans overlap in remarkable ways in the recent past. In particular, the MRCA of all present-day ...Missing: misconceptions | Show results with:misconceptions
[42]
Evidence that two main bottleneck events shaped modern human ...
Oct 7, 2009 · We find evidence of two primary events, one 'out of Africa' and one placed around the Bering Strait, where an ancient land bridge allowed passage into the ...Missing: 60000-70000 | Show results with:60000-70000
[43]
Eurasian back-migration into Northeast Africa was a complex and ...
Nov 8, 2023 · They found that ancient East African hunter-gatherers form a cline of ancestry with modern-day southern African hunter-gatherer (San) groups.Missing: 2023-2025 | Show results with:2023-2025
[44]
The nature of the last universal common ancestor and its impact on ...
Jul 12, 2024 · Age estimates for LUCA are usually based on the fossil record, varying with every reinterpretation. The nature of LUCA's metabolism has proven ...
[45]
https://pmc.ncbi.nlm.nih.gov/articles/PMC10631636/
[46]
Number of ancestors and length of identity-by-descent tracks over time
Aug 29, 2024 · This study focuses on small, insular populations, where the number of genetic ancestors can swiftly encompass the entirety of genealogical ...Missing: point | Show results with:point
[47]
[PDF] to what extent does genealogical ancestry imply genetic ancestry?
Recent statistical and computational analyses have shown that a genealogical most recent common ancestor (MRCA) may have lived in the recent past [4, 15].
[48]
Genetic evidence and the modern human origins debate | Heredity
Mar 5, 2008 · ... most recent common ancestor of humanity for a given haplotype and ... last common ancestor of modern humans and Neandertals. They found ...Missing: terminology | Show results with:terminology
[49]
A general and efficient representation of ancestral recombination ...
Nov 4, 2023 · As a result of recombination, adjacent nucleotides can have different paths of genetic inheritance and therefore the genealogical trees for ...
[50]
The complex genetic landscape of southwestern Chinese ... - Frontiers
Other six ancestral components contributed to the mosaic ancestry composition of modern and ancient East Asians and their geographical neighbors (Figure 1B).<|control11|><|separator|>