Organism Adaptations: Terrestrial and Aquatic Survival Strategies

Posted on Sep 4, 2025 in Biology

Terrestrial Environment Adaptations

Light creates stratification in photosynthetic organisms based on their needs. Species requiring more light develop in upper strata, while those needing less light occupy lower strata.
Many plants exhibit targeted movements in relation to light, known as phototropisms.
Light also affects animal activity. The alternation of days and nights influences animal behavior and activity. Many animals are active only during the day, while others are nocturnal.

Annual plants die in unfavorable seasons, leaving only seeds.
The activity of many trees decreases, and they lose their leaves. Plant buds can withstand temperatures as low as -25 degrees Celsius.
Homeothermic animals (birds and mammals) maintain a constant internal temperature. They possess various insulating structures such as hair, feathers, or thick layers of fat.
Some animals, like bears and marmots, hibernate, entering a state of reduced activity during winter.
Sweating in mammals is an adaptation to heat. Some mammals are nocturnal, an adaptation to avoid daytime heat.
In unfavorable conditions, poikilothermic animals (whose body temperature is similar to their environment) may migrate, enter a state of lethargy, or remain buried in a larval state.

Hydrophilic plants, found in very humid and dark environments, possess thin epidermises and abundant stomata to facilitate the loss of excess water.
Xerophytic plants, such as cacti and some thistles, live in dry environments. Their leaves are often modified into spines or have a thick, waxy cuticle to minimize water loss. Many develop succulent leaves or stems to store water.
Animals have special structures that prevent water loss through transpiration, such as the exoskeleton of arthropods, the scales of reptiles, or the hair of mammals.

Water absorbs solar radiation unevenly across the spectrum. This leads to photosynthetic organisms being distributed based on their pigments’ ability to capture light energy. Some thrive in well-lit areas, while others adapt to darker zones.
Many animals living in deeper, darker areas have developed specific organs to produce light. This capability is called bioluminescence.

Many fish possess a swim bladder, which helps them adapt to different pressures and float easily.
Organisms that live in deep areas often have a flattened shape and small internal cavities.

Some animals, such as salmon or eels, live in both marine and freshwater environments. They are able to regulate their internal salt concentration and maintain it constantly despite variations in the external saline medium due to osmotic processes. This allows them to live in waters of different salinities.

Organisms that float in water often have a large body surface area and may possess very branched prolongations or extensions.
Swimmers often have fusiform (spindle-shaped) bodies and paddle-shaped limbs.
Some, such as cephalopods, use propulsion mechanisms for travel.
Certain plants and algae have small bladders filled with air, allowing them to float and remain near the surface to capture light.

Aquatic plants have flexible stems that do not break with the flow of water.
Benthic organisms generally have flattened shapes or possess appendages or suction cups that allow them to anchor to the bottom.