Why do cockroaches sometimes standstill at a place?

Interestingly cockroaches are among the fastest insects on earth, with speeds up to 3.5 miles an hour. However, I have recently noticed that cockroaches sometimes standstill at a place like they are frozen. This fascinated me enough to research it, but sadly I found nothing on the internet. However, my brother in law who has studied zoology gave me some pretty clever answers.

Cockroaches sometimes standstill in a posture, also known as the hyper-extended postures, due to neck lesions (Reference). The other reason for standing still are either,

  1. The cockroach is in it’s resting state with no significant sensory input from the enviroment to feel the roach threatend.
  2. The cockroach is shedding its exoskeleton (molting).
  3. A female cockroach is giving birth/laying ootheca.

Some peers out there on the internet think that cockroaches are telepathically communicating with the other roaches when standing still. First, let me make you clear that cockroaches have a brain that has evolved only to provide basic survival instincts. They lack emotions and higher brain functions like memory, critical thinking, and logical reasoning.

Cockroach standing up; posture

A cockroach standing up in a peculiar upright posture is also known as the defensive posture. In this posture, the cockroach uplifts the front by extending two pairs of legs at the front while flexing the single back pair. The posture resembles a ninja preparing to fight.

This standing posture is not common to roaches but is also observed in several insects, including beetles and crickets.

The cockroaches are known to stand in this posture for days.

If you can’t sleep with a cockroach in your room, Read this article.

Cockroaches sometimes standstill; explained with Reasons

Sometimes we come across roaches standing still for hours like they are frozen in time or are dead. Then, when we try to approach a standing roach, it swiftly hides away. So what’s the reason for this peculiar behavior?

Lets me share a few possible explanations,

1. Neck lesion

One study published in the Journal of Comparative Physiology studied the effects of neck and circumoesophageal connective lesions on posture and locomotion in the cockroach.

The study concluded that cockroaches with neck lesions had hyper-extended postures and did not walk. However, soon after the recovery, the roaches had a less hyper-extended posture and initiated slow leg movements for multiple cycles.

2. Lack of External Stimuli

Cockroaches move in response to changes in temperature, vibration, and light. When no stimulus is interrupting, the cockroach adapts itself into a resting state. This is most likely the reason you see a cockroach standing still and immediately moves once you approach.

3. Moulting

The baby roaches, including the palmetto bugs, have to undergo between 5 to 8 stages of molting before transforming into adults. Once the desquamation starts, the cockroach most likely adopts a standing still posture.

4. Laying eggs

Once the female cockroach mates, it takes approximately 30 days to lay eggs. Once the process of egg-laying starts, it can take hours which requires a roach to stand still upright.

Additional Read!