Scorpions are unusual among arachnids because they give birth to live young (viviparity). The newborns, often called scorplings, are born in large broods that can range from a few dozen to over one hundred individuals. This unique method of reproduction is followed by a period of parental care where the mother transports her offspring, which is rare in the arthropod world. The duration of this maternal attachment is biologically driven by the scorpling’s early development.
Life on the Mother’s Back
The birthing process requires the mother to create a protected space, often described as a “birth basket,” using her legs and pedipalps. As the scorplings emerge, they are soft, pale, and vulnerable, sometimes encased in a thin embryonic membrane they quickly shed. Immediately after birth, the young instinctively clamber up their mother’s legs and onto the safety of her back.
This protective perch, known as the maternal transport stage, is a necessity because the scorplings’ outer layer, or exoskeleton, is still extremely soft. This soft cuticle makes them highly susceptible to desiccation (loss of body moisture) and predation. During this time, they are entirely dependent on their mother for protection and a stable environment, relying on residual yolk reserves rather than feeding or drinking.
The Critical First Molt
The period of riding on the mother’s back is determined by a significant developmental event: the first molt. This event is the biological timer for separation and typically takes place between one to three weeks after birth, though the exact timing varies by species and environmental conditions. For many common species, this stage lasts approximately 10 to 20 days.
Molting is the process of shedding the entire outer exoskeleton. Before this event, scorplings are considered first instars, a stage that is more of an extension of their embryonic development. The successful completion of this first molt transforms them into second instars, which possess a newly hardened and more robust exoskeleton. This stronger cuticle provides the necessary physical support and protection for a life away from the mother.
The first molt is the physical trigger for independence because the scorplings are now structurally mature enough to survive on their own. Their appendages and sensory organs become fully functional, allowing them to move quickly and perceive their environment. Once the new exoskeleton has fully hardened, which can take several days, the mother’s back is no longer a necessity for survival.
Independence and Life After Dispersal
Once the first molt is complete and the young have transitioned into second instars, they begin to disperse from the maternal shelter. This dispersal is usually a gradual process, with scorplings climbing down and scattering rapidly to seek their own hiding places. They are now fully formed, miniature versions of the adult, equipped to face the challenges of their solitary existence.
The young scorpions must immediately begin to forage, hunting for small insects and other arthropods. This marks the beginning of their independent life, which is characterized by a high degree of risk. The first few weeks after dispersal are a vulnerable time, and many young scorplings do not survive due to predation, harsh environmental conditions, or a lack of suitable prey.