Evidence of common descentEvidence of common descent of living organisms has been discovered by scientists researching in a variety of disciplines over many decades, demonstrating that all life on Earth comes from a single ancestor. This forms an important part of the evidence on which evolutionary theory rests, demonstrates that evolution does occur, and illustrates the processes that created Earth's biodiversity. It supports the modern evolutionary synthesis—the current scientific theory that explains how and why life changes over time.
MaladaptationIn evolution, a maladaptation (ˌmælædæpˈteɪʃən) is a trait that is (or has become) more harmful than helpful, in contrast with an adaptation, which is more helpful than harmful. All organisms, from bacteria to humans, display maladaptive and adaptive traits. In animals (including humans), adaptive behaviors contrast with maladaptive ones. Like adaptation, maladaptation may be viewed as occurring over geological time, or within the lifetime of one individual or a group.
Pression de sélectionvignette| Différents modes de sélection naturelle selon la pression sélective exercée par les conditions environnementales. Au cours de l'évolution des stratégies de prédation, une pression évolutive (ici le repérage visuel par la proie de la coloration de la fourrure du loup) oriente la sélection naturelle en faveur des adaptations (ici le camouflage du loup en fonction du milieu) qui permettent de favoriser la prédation, laquelle à son tour exerce une pression de sélection en faveur de différents types de défenses anti-prédation.
Eukaryote hybrid genomeEukaryote hybrid genomes result from interspecific hybridization, where closely related species mate and produce offspring with admixed genomes. The advent of large-scale genomic sequencing has shown that hybridization is common, and that it may represent an important source of novel variation. Although most interspecific hybrids are sterile or less fit than their parents, some may survive and reproduce, enabling the transfer of adaptive variants across the species boundary, and even result in the formation of novel evolutionary lineages.
Evolution of biological complexityThe evolution of biological complexity is one important outcome of the process of evolution. Evolution has produced some remarkably complex organisms – although the actual level of complexity is very hard to define or measure accurately in biology, with properties such as gene content, the number of cell types or morphology all proposed as possible metrics. Many biologists used to believe that evolution was progressive (orthogenesis) and had a direction that led towards so-called "higher organisms", despite a lack of evidence for this viewpoint.
Molecular ecologyMolecular ecology is a field of evolutionary biology that is concerned with applying molecular population genetics, molecular phylogenetics, and more recently genomics to traditional ecological questions (e.g., species diagnosis, conservation and assessment of biodiversity, species-area relationships, and many questions in behavioral ecology). It is virtually synonymous with the field of "Ecological Genetics" as pioneered by Theodosius Dobzhansky, E. B. Ford, Godfrey M. Hewitt, and others.
Chrono-espèceUne chrono-espèce est un groupe d'une ou plusieurs espèces dérivées d'un modèle d'évolution qui implique des changements continus et uniformes à partir d'une forme ancestrale disparue. Cette suite de modifications génère une population qui est physiquement, morphologiquement ou génétiquement distincte de ses ancêtres originels. Il n'existe qu'une seule espèce de la lignée à un moment donné : il ne s'agit donc pas d'une évolution divergente, qui produit différentes espèces vivant en même temps à partir d'un ancêtre commun (exemple des pinsons de Darwin).
