Mealworms are sometimes referred to as “golden grubs”. These high protein larvae make nutritious food for birds, reptiles, amphibians, or small animals. Grubco mealworms are nearly 20% protein. Mealworms come in different sizes to satisfy different appetites and animals. Small mealworms are about 1/2″, and medium mealworms range between 1/2″ to 3/4″. Medium mealworms will always fall into a constant range in size. After all, mealworms are a living and constantly growing animal. Mealworms will continue to grow and eventually turn to beetles if kept at room temperature or will become dormant if refrigerated.