Why are Seeds of Different Sizes and Shapes?

Evolution, adaptation to newer areas cause variance in physical traits

Seeds come in different sizes and shapes across plant species. They range from dust-sized seeds in orchids to double coconut Lodoicea (yes, coconuts are seeds!). This Sustainable, Secure Food Blog explores different types of sizes of seeds and how they’ve evolved. The post is part of the 2021 Seed Week celebration, organized by the Crop Science Society of America

According to blogger Aniruddha Maity, “depending on geographical location and the prevailing biotic and abiotic factors, seed size and shape can vary even within a species. Even within same species, for example corn, the size, shape, and shininess of the seeds vary.”

Seeds usually have three main parts:

  1. seed coat that protects the inner parts from outside hazards,
  2. embryo that grows to a plant, and
  3. endosperm (grasses) or cotyledon (non-grass) that stores and supplies food to the growing embryo.

Scientists have found smaller seeds have shorter dormancy lifespans than larger seeds because they contain less food inside. They need to stay near the soil surface so the smaller embryo can pierce through the soil. Larger seeds can stay in greater depth in soil. The depth at which a seed is planted depends on the shape of the seed as well.

Smaller seeds can travel to new geographical locations as they can fly to other areas or attach to clothing or your shoes. Big seeds do not tend to travel. To read more about seed shapes and sizes, read the entire blog: https://sustainable-secure-food-blog.com/2021/03/22/why-are-seeds-of-different-sizes-and-shapes/