Have you ever noticed how so many things in nature are symmetrical? From leaves to starfish to snowflakes, symmetry in nature can be found everywhere. While being visually appealing, this symmetry can also be explained for various reasons.
Several types of symmetry can be found in nature. Spherical symmetry is only found in certain microscopic creatures and algae, such as heliozoa and volvox. Radial symmetry, symmetry radiating around a central axis, can be seen in several different species of plants and animals, such as starfish and many flowering plants. Bilateral symmetry, symmetry down a single axis that divides the subject into two identical halves, is observed in many animal species, including humans.
In many plants and animals, their symmetry is influenced by long-term evolutionary patterns. In plants, bilateral symmetry (for example in a leaf) versus radial symmetry (as in a flower) is influenced by the different roles and processes that the part is involved in. The genes of the plant influence the symmetrical shape of the leaves and flowers as a response to the photosynthetic needs of the plant: the shape of a plant’s organs evolved over time to maximize their ability to photosynthesize, which created their symmetrical patterns.
Along with the biological processes that symmetry is involved in, symmetry in animals is likely mainly a result of mate selection and evolution. It has been suggested that humans find symmetrical people more attractive, likely meaning that symmetry in mammals has been influenced by mate choice. Since humans base many of their choices on visual stimuli, early humans choosing mates based on symmetry would strongly influence how modern humans have evolved.
Another beauty of nature that exhibits symmetry is snowflakes. However, snowflakes don’t have genes or evolution to influence their symmetry. Instead, snowflakes’ shape is influenced by the organization of water molecules and their bonds. Water molecules bond to each other with weak hydrogen bonds, which results in the hexagonal shape of the snowflake. The overall shape of the snowflake is strongly influenced by the atmospheric conditions that it forms in. For example, higher temperatures (23 degrees Fahrenheit) create long, thin crystals and lower temperatures (5 degrees Fahrenheit) cause flatter crystals. As the snowflake continues to fall, changes in temperature and humidity cause it to crystallize in different ways, creating the flake’s unique look.
As we can see, symmetry can be found in nature almost everywhere you look. Next time you go outside, make sure to take a look at the natural patterns all around you!
About The Author
Oliver Ewy is currently a junior at Northwood High School. He has an interest in various scientific fields and would like to work in medicine in the future.
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