Cross-Adaptation: Mastering Skills in New Environments
Cross-adaptation is the process of adapting a preexisting behavior or skill to a new environment or situation. It is a key concept in evolutionary biology, neuroscience, and cognitive psychology, and has important implications for understanding learning and adaptation in humans and animals. In evolutionary biology, cross-adaptation is the process by which a species evolves into […]
Panmixia: Is Love Truly Just a Game of Chance?
Random Mating The Concept of Random Mating Random mating, also known as panmixia, describes a fundamental mating system within a population where individuals select their partners without any consideration for genetic relationship, genotype, or phenotype. In such a system, any individual has an equal probability of mating with any other individual of the opposite sex […]
PROXIMATE EXPLANATION
Introduction to Proximate Explanations In the expansive fields of psychology and biology, understanding the intricate tapestry of behavior and biological phenomena necessitates a multifaceted approach. Among the fundamental explanatory frameworks, proximate explanations stand as a cornerstone, offering profound insights into the immediate, mechanistic causes underlying observed traits and actions. Unlike their ultimate counterparts, which delve […]
EVOLUTION OF THE BRAIN
Evolution of the Brain: A Comprehensive Definition The evolution of the brain is defined as the multi-millennial, cumulative process through which the nervous systems of living organisms, particularly vertebrates and primates, have undergone structural and functional transformations to reach higher levels of complexity. Spanning hundreds of millions of years, this biological odyssey has transitioned life […]
SELECTIVE ADAPTATION
The Conceptual Framework of Selective Adaptation Selective adaptation stands as a foundational biological and evolutionary process through which living organisms, across successive generations, develop and refine traits that significantly enhance their survival and reproductive efficacy within specific environmental contexts. This concept serves as a cornerstone of modern biological science, providing a comprehensive explanation for how […]
MATING SYSTEM
The Biological and Evolutionary Significance of Mating Systems In the vast field of evolutionary biology, mating systems represent the structured patterns of social and reproductive behavior that dictate how individuals within a species acquire mates and produce offspring. These systems are not merely social constructs but are fundamental drivers of a species’ evolutionary trajectory, influencing […]
THERMAL SENSITIVITY
An Introduction to Thermal Sensitivity and Its Biological Significance The concept of thermal sensitivity represents a cornerstone of biological and psychological inquiry, defining the inherent capacity of an organism to detect, interpret, and respond to fluctuations in environmental and internal temperatures. This multi-faceted trait is not merely a passive sensory experience but an active physiological […]
MULLERIAN MIMICRY
The Definition and Conceptual Framework of Mullerian Mimicry Mullerian mimicry represents a sophisticated evolutionary strategy wherein two or more distinct species, all of which possess some form of unpalatability or noxious defense, evolve to share a nearly identical warning signal. This phenomenon is categorized as a form of mutualism because it provides a collective survival […]
EXAPTATION
Exaptation is a term used to refer to the process of evolution that occurs when a trait or characteristic is used for a purpose that is different from the one it was originally adapted for (Dawkins, 2004). This concept was first introduced by Stephen Jay Gould and Elizabeth Vrba in 1982 as a way to […]
REPRODUCTIVE TYPE
Introduction to the Concept of Reproductive Type In the vast fields of ecology and evolutionary biology, the term reproductive type serves as a fundamental framework for understanding how organisms propagate their genetic legacy across generations. This concept does not merely describe the act of birth or division but encompasses the entire suite of biological mechanisms […]
BALDWIN EFFECT
Foundations and Historical Context of the Baldwin Effect The Baldwin effect represents a sophisticated evolutionary theory that describes the process by which an organism’s ability to learn new behaviors can eventually influence the genetic makeup of its species over successive generations. Named after the American psychologist and biologist James Mark Baldwin, who first articulated the […]
FECUNDITY
Definition and Theoretical Significance Fecundity, fundamentally defined as the reproductive potential of an organism, represents the maximum number of offspring that a female can theoretically produce over her entire lifespan under optimal conditions. This biological trait is not merely an indicator of productivity but serves as a cornerstone for understanding species survival, population dynamics, and […]
BEHAVIORAL HOMOLOGY
Introduction to Behavioral Homology and its Definition Behavioral homology is a foundational concept within the fields of ethology, comparative psychology, and evolutionary biology, referring to the similarity of a specific behavioral trait observed in two or more species that is attributable to their inheritance from a common ancestor. This principle posits that just as morphological […]
CONVERGENT EVOLUTION
CONVERGENT EVOLUTION Convergent evolution is a fundamental process in evolutionary biology defined by the independent emergence of similar characteristics in species that are not closely related phylogenetically. This phenomenon occurs when disparate organisms are subjected to similar environmental pressures and ecological challenges, thereby driving natural selection toward comparable adaptive solutions. The resulting similar traits, whether […]
LAW OF FILIAL REGRESSION
LAW OF FILIAL REGRESSION The Law of Filial Regression, as defined within this specific evolutionary framework, is a powerful conceptual tool introduced by the renowned evolutionary biologist Ernst Mayr in his seminal 1963 work, Animal Species and Evolution. This concept was developed not to address the statistical phenomenon of traits reverting toward a population mean, […]
CONSILIENCE
Definition and Historical Origins Consilience is a profound concept in the philosophy of science, denoting the convergence of evidence from multiple, independent, and often disparate sources upon a single conclusion, hypothesis, or theoretical framework. This powerful intellectual mechanism suggests that the truth is more likely to be found when different lines of inquiry, employing distinct […]
BODY-TYPE THEORIES
BODY-TYPE THEORIES Body-type theories represent a significant, though often controversial, tradition within the history of psychology, anthropology, and medicine. These theories operate on the premise that human physical structure can be systematically categorized, and, crucially, that these physical classifications correlate directly with distinct psychological traits, temperaments, or behavioral tendencies. The underlying goal of these systems […]
MEGA-
MEGA-: A Review of its Origins and Applications The term “MEGA” refers to the “Molecular Evolutionary Genetics Analysis” software package, which is a comprehensive suite of computer programs used for a wide range of molecular evolutionary genetic analyses (Kumar, 2016). This article reviews the history of the MEGA software, its applications, and its current role […]
LICKING BEHAVIOR
Introduction to Licking Behavior Research The act of licking represents a complex behavioral repertoire observed across a vast range of species within the mammalian class and beyond. Far from being a simple motor reflex, licking integrates sophisticated sensory processing, motor control, and cognitive evaluation, making it a critical subject in ethology, comparative psychology, and neuroscience. […]
WINNER EFFECT
The Winner Effect: Definition and Scope The Winner Effect is a deeply researched psychological and biological phenomenon describing how success in a competitive environment significantly increases the probability of subsequent success. It posits that victory initiates a positive feedback loop, enhancing an individual’s confidence, physiological preparedness, and overall performance capability in future contests. This effect […]
LIFE HISTORY
Introduction: Definition and Scope of Life History Theory (LHT) Life History Theory (LHT) represents a fundamental conceptual framework within evolutionary biology, defining the trajectory of an organism through time (Stearns, 1992). It seeks to understand how natural selection shapes the key schedules and timing of biological events, including the age and size at birth, the […]
BIPARENTAL CARE
Introduction to Biparental Care Biparental care constitutes a crucial reproductive strategy across the animal kingdom, defined fundamentally as a system in which both parents actively participate in providing resources, protection, and instruction necessary for the survival and development of their offspring. This cooperative approach contrasts sharply with the more common strategy of uniparental care, typically […]
OPERATIONAL SEX RATIO
Definition and Core Concepts of the Operational Sex Ratio (OSR) The concept of the Operational Sex Ratio (OSR) serves as a fundamental metric in behavioral ecology and evolutionary biology, providing crucial insight into the dynamics of competition and mate choice within a population. Defined precisely, the OSR is the ratio of sexually active males available […]
PHYLOGENETIC PRINCIPLE
The Phylogenetic Principle: Definition and Historical Context The Phylogenetic Principle stands as a foundational, albeit highly debated, theory in the history of biology and developmental psychology. It posits that the developmental history of an individual organism, known as ontogeny, tends to recapitulate the evolutionary history of its species, termed phylogeny. This concept is most famously […]
PEDOMORPHOSIS
Introduction and Definition of Pedomorphosis Pedomorphosis, derived from the Greek words meaning ‘child’ (pais) and ‘form’ (morphe), is a specialized term in developmental biology and psychology referring to the retention of juvenile characteristics in the adult stage of an organism. This phenomenon is a type of heterochrony, which is any evolutionary change in the timing […]
DARWINISM
Definition and Historical Context Darwinism refers fundamentally to the theory of evolution driven primarily by natural selection, a revolutionary concept proposing that species change over geological timescales through mechanisms of variation, inheritance, and differential survival. While the idea of species transmutation existed prior to the mid-nineteenth century, it was the meticulous empirical framework provided by […]
COOPERATIVE BREEDING
Defining Cooperative Breeding and Alloparenting Cooperative breeding represents a specialized and complex social strategy observed across various taxonomic groups, wherein a breeding pair typically monopolizes the majority of reproduction, while other adult or subadult members of the group, known as auxiliaries or helpers, actively participate in the critical tasks associated with rearing the offspring. This […]
BATESIAN MIMICRY
Introduction to Batesian Mimicry Batesian mimicry is a profound and widely studied phenomenon within the fields of evolutionary biology and behavioral ecology, representing a critical survival strategy employed by numerous species across various taxa. Defined fundamentally as a form of biological resemblance where a palatable, harmless, or less-defended species (the mimic) evolves to imitate the […]
PREFORMISM
Introduction and Definition of Preformism Preformism, derived conceptually from the Latin meaning "formed beforehand," stands as a historically dominant yet ultimately discredited biological theory concerning the process of organic development and generation. This theory, which reached its zenith of popularity during the 17th and 18th centuries, fundamentally posited that the entire organism, encompassing all its […]
SELFISH HERD
Definition and Core Principles The concept of the Selfish Herd describes a specific pattern of animal collective behavior wherein individuals aggregate primarily for personal safety rather than communal benefit or explicit cooperation. This ethological model, first proposed by evolutionary biologist W. D. Hamilton in 1971, posits that group formation is an emergent property arising from […]
DIVERGENT EVOLUTION
Introduction to Divergent Evolution Divergent evolution represents a fundamental process within evolutionary biology, describing the manner by which populations originating from a common ancestor become increasingly dissimilar over geological time, typically in response to varied environmental pressures or habitat differences. This mechanism is central to the generation of biodiversity, serving as the primary engine through […]
FLUCTUATING ASYMMETRY
Defining Fluctuating Asymmetry Fluctuating Asymmetry, often abbreviated as FA, is a highly specialized term utilized across evolutionary biology, developmental biology, and physical anthropology. It describes the subtle, random deviations from perfect bilateral symmetry that occur in morphological traits across the midline of an organism. Crucially, FA is defined specifically by the condition where the mean […]
KIN SELECTION
Introduction to Kin Selection: The Paradox of Altruism Kin selection represents a fundamental cornerstone of modern evolutionary biology, offering a powerful explanation for the persistence of seemingly altruistic behaviors observed across the animal kingdom. At its core, kin selection is defined as natural selection that favors behavior by an individual that increases the reproductive success […]
SPERM COMPETITION
Definition, Scope, and Evolutionary Foundations Sperm competition is fundamentally defined as the rivalry occurring between the spermatozoa of two or more different males to successfully fertilize a single set of ova, following the mating of a female with multiple partners. This phenomenon is a crucial component of post-copulatory sexual selection, acting after copulation has occurred […]
SEXUAL AGGRESSION
Definition and Scope of Sexual Aggression Sexual aggression is defined broadly across biological and psychological disciplines as aggressive behavior exerted by one sex toward the other, specifically aimed at achieving sexual contact or copulation without the complete, voluntary consent of the recipient. In zoology and ethology, this phenomenon is often observed in species exhibiting pronounced […]
PARENTAL INVESTMENT
Definition and Theoretical Foundations Parental Investment, in the context of evolutionary psychology and behavioral ecology, is defined as any expenditure of energy or resources by a parent on an individual offspring that increases the offspring’s chance of survival and future reproductive success, but simultaneously decreases the parent’s ability to invest in other offspring, either current […]
ASSORTATIVE MATING
Definition and Core Concepts Assortative mating is a fundamental biological and psychological mechanism defined as a non-random mating pattern where individuals select partners based on the presence or absence of specific phenotypic or genotypic characteristics. This process dictates that the choice of a mate is predicated on traits such as attractiveness, shared cognitive abilities, similar […]
STABILIZING SELECTION
Introduction to Stabilizing Selection Stabilizing selection represents a fundamental mode of natural selection that acts to maintain the existing average phenotype within a population over subsequent generations. Unlike directional selection, which favors traits at one extreme of the phenotypic distribution, or disruptive selection, which favors both extremes, stabilizing selection actively selects against individuals exhibiting extreme […]
ATAVISM
Introduction and Definition of Atavism: The Concept of Reversion The term atavism (from the Latin atavus, meaning great-great-great-grandfather or ancestor) describes the striking reappearance of a trait that had been absent for generations, manifesting a reversion to an earlier type. This concept holds significant weight across both biological sciences, particularly genetics and evolutionary developmental biology, […]
PHILOPATRY
Definition and Core Concepts of Philopatry Philopatry, derived from the Greek meaning “love of one’s fatherland,” is a specialized term used primarily in ecology, ethology, and behavioral biology, though its implications often touch upon human psychology and sociology. Fundamentally, it describes the adherence, loyalty, or strong tendency of an organism to remain in or habitually […]
SEXUAL DIMORPHISM
Defining Sexual Dimorphism Sexual dimorphism refers to the systematic differences observed between males and females of the same species, extending beyond the mere distinction of primary sexual characteristics, which are the reproductive organs necessary for procreation. Fundamentally, it describes the existence within a species of males and females that are measurably different from one another. […]
MALADAPTATION
Introduction and Core Definition of Maladaptation The term maladaptation in psychological and biological discourse refers to a condition where inherent characteristics, responses, or mechanisms—spanning biological, psychological, behavioral, and defensive domains—are demonstrably detrimental to the survival, well-being, or reproductive success of an organism or a species. Maladaptation signifies a failure of an evolved or acquired trait […]
RUNAWAY SELECTION
Introduction and Core Definition of Runaway Selection The hypothesis of Runaway Selection, often referred to as Fisherian Runaway Selection, provides a compelling explanation within evolutionary biology and psychology for the development of sexually dimorphic traits that appear exaggerated or even detrimental to the survival of the organism. This theory posits that certain attributes in males, […]
RESOURCE DEFENSE POLYGYNY
Resource Defense Polygyny The Core Definition of Resource Defense Polygyny Resource Defense Polygyny (RDP) is a specific type of Polygyny, a Mating System in which one male mates with multiple females, driven by the male’s ability to monopolize access to critical resources required by the female population. Fundamentally, RDP occurs when resources necessary for female […]
DARWINIAN FITNESS
Darwinian Fitness The Core Definition of Darwinian Fitness Darwinian fitness, often simply termed evolutionary fitness, is a fundamental concept in biology and evolutionary psychology that quantifies the reproductive success of an organism relative to the rest of the population. Proposed originally by Charles Darwin, it is not a measure of physical strength, speed, or intelligence […]
SELFISH GENE HYPOTHESIS
SELFISH GENE HYPOTHESIS The Core Definition of the Selfish Gene The Selfish Gene Hypothesis (SGH) posits a profound shift in perspective regarding the primary unit of Natural Selection. Instead of viewing the organism or the group as the central focus of evolutionary change, the hypothesis asserts that the gene itself is the fundamental unit of […]
FEMALE CHOICE
Female Choice in Evolutionary Psychology and Behavioral Ecology The Core Definition of Female Choice Female choice, scientifically known as intersexual selection, is the selective pressure exerted by females on the reproductive success of males within a species. It is a critical, often dominant, component of sexual selection, a process originally described by Darwin where certain […]
RECIPROCAL ALTRUISM
Reciprocal Altruism The Core Definition of Reciprocal Altruism Reciprocal altruism is a theory of evolutionary psychology and sociobiology that explains the phenomenon of cooperative behavior between non-kin individuals. Fundamentally, it describes a type of helping behavior where an organism provides a benefit to another at a cost to itself, with the expectation that the recipient […]
EVOLUTIONARILY STABLE STRATEGY (ESS)
Evolutionarily Stable Strategy (ESS) The Core Definition of ESS The Evolutionarily Stable Strategy (ESS) is a central concept in evolutionary biology and behavioral ecology, derived from the mathematical discipline of game theory. It defines a behavioral strategy or mixture of strategies that, if adopted by almost all members of a population, cannot be successfully invaded […]
REPRODUCTIVE BEHAVIOR
Reproductive Behavior: An Encyclopedia Entry The Core Definition of Reproductive Behavior Reproductive behavior encompasses the entire suite of actions, interactions, and physiological processes exhibited by animals, including humans, specifically aimed at perpetuating the species through sexual or asexual reproduction. It is a fundamental element of the life cycle across nearly all biological kingdoms, ensuring genetic […]
RELATIVE ACCOMMODATION
Relative Accommodation Defining Relative Accommodation Relative Accommodation (RA) is a multidisciplinary theoretical framework utilized to describe the dynamic processes through which an individual organism, population, or system adjusts successfully to shifting internal or external environmental conditions. At its core, RA is intrinsically linked to the concept of Relative Fitness, which measures an organism’s reproductive success […]
REPRODUCTIVE SUCCESS
Reproductive Success The Core Definition of Reproductive Success Reproductive success is a foundational concept within evolutionary biology and evolutionary psychology, serving as the central metric by which an organism’s evolutionary fitness is ultimately measured. Defined fundamentally as the capacity of an individual to pass its genes to subsequent generations, reproductive success is quantified by the […]
SEXUAL SELECTION
Sexual Selection The Core Definition of Sexual Selection Sexual selection is a specific and powerful mode of evolutionary change characterized by competition for mates, which results in differential reproductive success among individuals within a population. Simply put, it is the process by which certain individuals are consistently chosen over others for mating, often due to […]
ESSENTIALISM
Essentialism is the philosophical belief that certain entities have essential properties which are necessary to their identity and function. Essentialism is a fundamental part of many religious and metaphysical beliefs. It is also a major component of some scientific theories, such as those of quantum mechanics and evolutionary biology. Essentialism has been criticized by some […]
SPECIES RECOGNITION
Species Recognition: A Review of Current Approaches Species recognition is an important field of study in ecology, conservation, and evolution. Species recognition is the ability to accurately discriminate between members of different species. It is a complex process that involves the analysis of physical traits, behavioral characteristics, and genetic information. In recent decades, advances in […]
SELFISHNESS
Selfishness: An Encyclopedia Entry The Core Definition of Selfishness Selfishness, in a psychological and behavioral context, is fundamentally defined as the excessive or exclusive concern with oneself, prioritizing one’s own needs, desires, welfare, or interests above those of others. While a degree of self-interest is essential for survival and healthy functioning, selfishness crosses the line […]
CRYPTIC FEMALE CHOICE
Cryptic Female Choice Introduction to Cryptic Female Choice Cryptic female choice (CFC) represents a sophisticated reproductive strategy observed across numerous species, wherein females exert a selective influence over the paternity of their offspring after copulation has occurred. This choice is termed “cryptic” because it involves mechanisms and decisions that are not overtly visible or easily […]
ONTOGENY
Ontogeny Introduction: The Core Definition of Ontogeny Ontogeny refers to the comprehensive study of the developmental processes an organism undergoes from its earliest inception, typically fertilization, through birth, maturation, and aging, all the way to its death. This profound branch of science offers critical insights into the intricate mechanisms governing the development, evolutionary biology, and […]
ANANDRIA
Anandria: Asymmetric Development of Sexual Dimorphism Introduction to Anandria The natural world is replete with examples of differences between males and females of the same species, a phenomenon broadly termed sexual dimorphism. These differences can range from subtle variations in size or coloration to striking disparities in anatomical structures, behaviors, or physiological processes. While many […]
RETROGRESSION
RETROGRESSION The Core Definition of Retrogression Retrogression, in the context of evolutionary biology, describes a process where a species or population reverts to earlier developmental stages or characteristics, effectively returning to a former or less complex state. This phenomenon challenges the common misconception of evolution as an inherently progressive, ever-advancing ladder of complexity, instead highlighting […]
EMERGENT EVOLUTION
Emergent Evolution The Essence of Emergent Evolution Emergent evolution, a fascinating and profound concept spanning multiple scientific disciplines, describes a type of evolutionary change where the interaction between components of a system produces novel and unexpected outcomes. At its core, it posits that when individual parts of a system interact, they can give rise to […]
MULTIPLE MATING
Multiple mating is defined as the process of mating with two or more partners over the course of an individual’s reproductive life (Delgado & Arim, 2017). This behavior has been observed in a wide variety of animal species, including mammals, birds, insects, and fish (Emlen & Oring, 1977; Clutton-Brock, 1989; Busch, 2009; Alonzo et al., […]
COURTSHIP BEHAVIOR
Courtship Behavior The Core Definition of Courtship Behavior Courtship behavior encompasses a diverse array of ritualized actions, displays, and communications exhibited by individuals across many species, including humans, with the primary purpose of attracting a potential mate and facilitating successful reproduction. It is a fundamental biological and psychological phenomenon that initiates and maintains pair bonds, […]
BIOLOGICAL DRIVE
Biological Drive: An Encyclopedia Entry Introduction to Biological Drive A biological drive represents an innate, unconscious motivation that compels an organism to engage in specific activities or seek particular objects in order to alleviate an internal physiological deficit or satisfy a fundamental biological need. These fundamental drives are deeply rooted in an organism’s biology, emerging […]
RECAPITULATION THEORY
Recapitulation Theory The Core Definition of Recapitulation Theory Recapitulation theory, often encapsulated by the phrase “ontogeny recapitulates phylogeny,” posits a provocative and historically significant hypothesis within the realm of biological development. At its most fundamental level, this theory suggests that the developmental stages of an individual organism (known as ontogeny) mirror, or “recapitulate,” the evolutionary […]
NEUROETHOLOGY
Neuroethology Introduction to Neuroethology: The Neural Basis of Behavior Neuroethology is a specialized and highly interdisciplinary branch of neuroscience that systematically investigates the neural mechanisms underlying complex and natural animal behavior. At its core, it seeks to understand how the nervous systems of various species interact with their specific environments to produce adaptive behaviors critical […]
ADAPTABILITY
Adaptability Introduction and Core Definition of Adaptability Adaptability is fundamentally defined as the capacity of an individual, group, or system to adjust effectively to new conditions, demands, or changes within its environment. It represents a dynamic process of modification and learning, enabling organisms to thrive or maintain functionality in the face of novelty or challenge. […]
DIMORPHISM
Dimorphism The Core Definition of Dimorphism Within the vast diversity of the biological world, dimorphism stands as a compelling phenomenon where two distinct forms of individuals exist within the same species. These forms are characterized by observable differences in morphology, physiology, or behavior, which are not merely individual variations but represent consistent, alternative expressions within […]
SPLIT RUN
Split Run The Core Definition of Split Run Methodology The concept of a split run, in its broadest scientific application, refers to a powerful experimental design method primarily employed to study the behavior of individuals or populations under varying conditions. At its heart, it involves the systematic division of a larger group into at least […]
NONADAPTIVE TRAIT
Nonadaptive Trait Introduction to Nonadaptive Traits In the vast and intricate tapestry of biological diversity, traits are typically viewed through the lens of their contribution to an organism’s survival and reproduction. However, not all characteristics held by a species offer a clear advantage or disadvantage in the struggle for existence. A nonadaptive trait is fundamentally […]
NATURAL SELECTION
Natural Selection Introduction: Defining Natural Selection Natural selection stands as a cornerstone concept within evolutionary biology, serving as one of the primary mechanisms driving the astonishing diversity and complexity of life observed across Earth. At its core, natural selection is the process through which individuals within a population that possess traits better suited to their […]
TROPHOTROPIC
Trophotropic Responses in Psychological Contexts The Core Definition: Trophotropic Principles in Psychology While the term trophotropic originates primarily in biological and ecological sciences, referring to an organism’s directed growth or movement in response to specific environmental stimuli, its underlying principles offer a valuable framework for understanding fundamental psychological processes. In a psychological context, trophotropic responses […]
ORTHOGENESIS
Orthogenesis Introduction to Orthogenesis Orthogenesis, also referred to as orthogenetic evolution, represents a historical concept within evolutionary biology proposing that evolutionary change occurs in a predetermined, single, and linear direction. This idea fundamentally posits that internal forces or mechanisms within an organism’s lineage guide its development towards a specific, often more complex or ‘perfected,’ form, […]
AROMATIZATION HYPOTHESIS
Aromatization Hypothesis The Core Definition of the Aromatization Hypothesis The Aromatization Hypothesis is a fundamental concept in neuroendocrinology and developmental biology, positing that the sexual differentiation of the brain and behavior in many vertebrate species is mediated not directly by androgens, but by the estrogens produced through the enzymatic conversion of androgens within specific brain […]