The noble gases already have a full outer shell. The noble gases break the trend by being less reactive than the elements to their left.
Ecologists are the persons who study the interrelationships between organisms and their environments. Like they research upon the species found in forests or deserts interact with each other and as well as their surroundings.
They test whether a species is occupying its complete fundamental niche or only a portion of it by observing if the species are expanding their range after the removal of a competitor because two species with the same fundamental niche will exclude other competing species.
I believe it is “animals and plants caanot directly use all the nitrogen found in our atmosphere”
Founder effect or population bottleneck refer to events which bring about reduction in the genetic variability of a particular specie population. Such events typically drastically reduce the gene pool of the population and produce a smaller number of population with less genetic diversity. An example of a population bottleneck is a genocide event. Such event will destroy a large percentage of the affected population leaving only a smaller population with less genetic diversity. i hope these helps.
