March 2025

Systematics: The term “systematics” is derived from the word “systema,” meaning the systematic arrangement of organisms. It considers the evolutionary relationships among organisms. Plant systematics, in particular, deals with the interrelations between plants and their evolutionary descent. Systematics studies biological diversity and organizes this information into a classification system. Organisms are classified based on similarities,…

Taxonomy, the science of classifying organisms, has evolved over centuries from simple groupings based on observable traits to complex systems incorporating evolutionary relationships and molecular data. The history of taxonomy can be divided into distinct phases, each marked by significant contributions from naturalists and scientists. 1. Early Classification Systems (Pre-Linnaean Period) a. Ancient Taxonomy (Aristotle…

Sytematics is commonly defined as the study of biological diversity and the relationships among organisms. Taxonomy, that component of systematics specifically focusing on the theory and practice of classification, is not clearly separable and both are frequently used interchangeably by biologists. This chapter will first briefly review the importance of systematics to the pest management…

Taxonomy, in a broad sense the science of classification, but more strictly the classification of living and extinct organisms i.e., biological classification. The term is derived from the Greek taxis (arrangement) and nomos (law). Taxonomy is, therefore, the methodology and principles of systematic botany and zoology and sets up arrangements of the kinds of plants and animals in hierarchies of superior and subordinate groups. Among biologists the Linnaean system of binomial nomenclature, created by Swedish naturalist Carolus Linnaeus in the 1750s,…

The Earth can be divided into distinct regions based on the presence or absence of various organisms. These regions are known as realms. Over time, different scientists have proposed various classifications of these realms. In 1857, P. L. Sclater categorized the Earth’s geographical areas into six regions based on bird distribution. Later, in 1876, Alfred…

Barriers and dispersal are fundamental concepts in zoogeography, the study of the geographical distribution of animals. They influence how species spread, adapt, and evolve in different regions. Barriers in Zoogeography: Barriers restrict or prevent the movement of species, influencing their distribution. They can be classified into: a. Physical (Geographic) Barriers: Oceans & Seas: Prevent land…

Animal distribution refers to how animal species are spread across different geographical regions. The distribution of animals is influenced by factors such as climate, habitat availability, competition, predation, geological changes, and evolutionary history.Animal distribution can be classified into several types based on their geographical spread and limitations. Cosmopolitan Distribution: Species with a cosmopolitan distribution are…

Zoogeography is the branch of biogeography that studies the geographical distribution of animal species across different regions of the world. It helps in understanding how animals are distributed, their evolutionary history, and the factors influencing their dispersal. 1. Descriptive Zoogeography Descriptive zoogeography is a branch of zoogeography that focuses on systematically documenting and describing the…

Zoogeography is the branch of biogeography that studies the distribution of animal species across different geographical regions and the factors influencing their dispersal. It provides insights into how species originated, migrated, and adapted to different environments. Importance of Zoogeography • Helps in understanding species distribution and biodiversity. • Assists in conservation biology by identifying species-rich…