Origin of organized structures
rubabIt took a long time for plants to develop proper roots and vascular system for land dwelling. These carry water drawn through roots to all parts of their bodies -…
MOLECULAR EVOLUTION
abidaThe structure and functions are observable on a large scale. Therefore, many evolutionists study changes in animal structure and function. - Its examples are change in the shape of bill…
Population Ecology – Definition & Key Points
sanaTERMS DEFINITIONS Population The number of individuals of specie living in the same area at the same time is called population. Monospecific Population of only one specie living in the…
The nature of evolutionary forces
The forces which bring about evolutionary changes by natural selection are called evolutionary forces. These forces are random genetic drift, gene flow and mutation. 1. Genetic drift The change in…
RATES OF EVOLUTION
There are two models of evolution based on the rate of evolution. The concept that evolutionary changes occurs gradually over millions of years is called phyletic gradualism. Charles Darwin believes…
REPRODUCTIVE STRATEGY
The basis of reproductive strategies is the survival of plant in particular habitat. These reproductive strategies are developed by natural selection. Every organism reproduces to maintain their specie. Each organism…
SPECIES AND SPECIATION
Definition of biological specie: Taxonomists classify organisms according to their similarities and differences. The fundamental unit of classification is the species. Unfortunately, it is difficult to define species. According to…
DEMOGRAPHY
The study of the vital statistics that affect population size is called demography. Birth rate and death rate vary among subgroups within a population. This birth rate and death rate…
SEED BANK
The storage of seed in the soil is called seed bank. Seeds fall on the soil. They are buried in the soil. Some seeds germinate to form the new plants.…
SEED DISPERSAL
Seed is an important source of dispersal of species of a plant to other places. Seeds are dispersed to far off places. Thus the genes of a population of plant…