8 topics with a brief review: definitions, key facts, and classroom questions.
This section focuses on the historical development of living systems and the mechanisms of their structural evolution. We study how organs form, adapt, and disappear across generations from the perspective of evolutionary morphology.
The materials cover all key concepts: from basic notions of analogous and homologous organs to complex processes of phylogenetic differentiation and integration. You will learn how organ functions transform, why convergent similarities arise, and how individual and historical development are linked through ontogenetic and phylogenetic correlations. Special attention is paid to reduction processes (vestigial organs and atavisms) and the theory of phylembryogenesis.
In practical classes and colloquia, students are most often asked to provide clinical or biological examples of vestigial organs and atavisms, clearly distinguish between homology and analogy, and explain the modes of phylembryogenesis (anaboly, deviation, arallaxis). Understanding these patterns is essential for successfully passing the evolutionary biology module.
This is a phenomenon where an organism repeats structural features or developmental stages of its ancient ancestral forms during its individual development.
What is the fundamental difference between analogous and homologous organs?
Analogous organs have different origins and structural plans, but perform a shared function due to similar living conditions. Homologous organs develop from common embryonic rudiments following a unified plan, but may perform completely different functions.
What is the multifunctionality of organs?
This is a principle where an organ performs multiple functions simultaneously, with one being primary and the rest secondary. This is a crucial prerequisite for any phylogenetic transformations.
What happens to the structure of an organ when its function is enhanced (intensified)?
The number of basic functional units increases, accompanied by an increase in organ size and reorganization of its histological structure (e.g., an increase in the number of mammary gland lobes).
What are genomic correlations?
This is the basis of all other correlations, determined by gene properties and interactions. The primary mechanism is pleiotropy (where a single gene affects multiple traits).
In which vertebrate groups are legless forms observed as an example of convergence?
The independent loss of limbs occurred in some amphibians (caecilians), as well as among various reptiles—in legless lizards (glass lizards) and snakes.
Master the entire topic in the "Biology" course
This is a summary. The course covers everything tested in classes and exams.
3,793 pages of study guides across all topics
Assignments and quizzes after every topic — just like in a colloquium