What is tolerance? What characterizes the tolerance curve?

Organisms living in a particular environment develop specific adaptations to the environmental conditions of this particular environment.
However, organisms have different tolerance (from lat. Tolerantia – patience) – the ability to withstand changes in living conditions (for example, fluctuations in temperature, humidity, light). This is a very important property of the living, allowing you to adapt to changing conditions.
Any environmental factor has certain limits on the positive impact on living organisms. For example, the body can die from too low or too high temperature. Graphs showing tolerance conditions are called tolerance curves. The position of the peak of the curve indicates the optimal (best) conditions for this factor for individuals of this species.
Some species are characterized by curves with very sharp peaks. This means that the range of conditions under which individuals of this species can normally exist is very narrow. Flat curves correspond to a wide range of tolerance.
Organisms with wide boundaries of sustainability, of course, have a chance of wider distribution. However, wide borders on one environmental factor do not at all mean wide borders on all factors. For example, many amphibians can withstand significant temperature fluctuations, but cannot even tolerate short-term drying of the skin.