An organism’s life history is the pattern of growth, development, and reproduction over the course of its life. Since fitness is a measure of the organism’s reproductive success, we know that natural selection will favour the life history strategy that results in the greatest number of offspring that survive to produce offspring of their own. … Continue reading Life History Strategies
A fundamental question in ecology is the question of how the vast diversity of species that we find on this planet originate. Key to this is the idea of reproductive isolation, or the group of mechanisms which prevent two groups of living organisms from breeding with each other. Reproductive isolation can be subdivided into … Continue reading Where Do New Species Come From?
The task of classification of organisms has remained a daunting task ever since we humans began to group what we consider to be closely related living beings together. In the mid 1700s, Swedish botanist, zoologist, and physician Carolus Linnaeus wrote the System Naturae, a way of organizing living beings into a hierarchical fashion. Combined … Continue reading What is a Species?
While Darwin and Wallace’s theory of evolution explains the vast diversity of species we see today, their theory doesn’t offer an explanation as to HOW life came to be on our planet 3.2 billion years ago. We know from looking at extant species today that certain properties of life are maintained and thus have been … Continue reading Origin of Life
Within much of western science prior to the 6th century BC, creation myths pervaded much of the answers to the creation of the universe and the species within it. Aristotle had proposed a taxonomy of nature. Amongst the Ancient Greeks, Empedocles had proposed an early form of spontaneous generation, where individuals were assembled from parts … Continue reading The History of Evolution and Natural Selection
Natural selection is the key mechanism through with evolutionary change occurs and has led to the near infinite modifications that we see in the biological diversity of the world today. In order for natural selection to occur, three conditions must be met. First, there must be variation - individuals differing from each other - within … Continue reading Natural Selection and Adaptation
The source of all essential nutrients is either in the atmosphere or in the form of rocks and minerals around us. These nutrients make their way through living and inorganic forms through nutrient cycling. As organisms are develop, they take in these nutrients and store them in their tissues and/or use them for life’s processes, … Continue reading Nutrient Cycling and Decomposition
All energy on the planet is governed by the laws of thermodynamics. The first law states that energy can be transferred but cannot be created nor destroyed. The second law states that while energy is transferred, a portion of it will be lost as heat energy. In the biological world, all energy begins it’s life … Continue reading Energetics and Ecological Productivity
Each environment an organism inhabits holds a different set of constraints for processes related to the survival, growth, and reproductive ability of a species. Different patterns of temperature, precipitation, seasonality, depth, salinity, pH, and dissolved oxygen among terrestrial and aquatic ecosystems are reflected in the different characteristics that an organism exhibits. These characteristics include the … Continue reading Organisms and their Environment
Ecology is the study of the relationship between organisms and their environment Ecology is the scientific study of the relationships between the processes behind an organism’s ability to survive, grow and reproduce, and the physical/chemical components (abiotic – temperature, moisture, oxygen concentration, light availability) and the biological/living components (biotic) of their environment. Stemming from the … Continue reading What is Ecology?