Naked Mole-Rat Estradiol

Figure1: A naked mole-rat eating and the queen in a naked mole-rat colony is the only existing mum (A).

A naked mole-rat burrow with several baby mole-rats and at least one adult mole-rat (B).

(Source: Hamers 2018).

Estradiol is defined as the primary female sex hormone, which is a form of estrogen hormone formed during the course of life development in both males and females (Hamers 2018). The hormone is usually produced frequently by the ovaries among adult women, which is required by the body for the preparation for the potential to reproduce. Roellig, Drews, Goeritz and Hildebrandt (2011) cast doubts on whether the mode of parental care in naked mole-rat species is altricial or reasonably precocial since the common standards for altricials being born sightless and ‘naked’ is understandably challenging to relate to this species. Therefore, the adult women are empowered to have a baby through the hormone’s influence as naked mole-rat eats in a naked mole-rat colony (see Figure 1). In the experiment demonstrated by the author, more secretion of estradiol from their individual dung was prevalent among naked mole-rats eating treated feces. The dominant queen along with 1–3 males are involved in the production of all of the pups in the naked mole-rats’ colony (Henry, Dengler-Crish and Catania 2007).

There are higher chances of altering the hormone levels, a hormonal boost, in the adult females as a result of eating on the poop packed with the hormone.

Key Points:

Estradiol hormone is commonly produced by the ovaries in adult female naked mole-rats.

The hormone is largely produced in dungs of naked mole-rats eating treated feces

Mole-rats spending a lot of time in nests have higher chances of eating their poop than those outside.

Introducing estradiol hormone in the subordinate naked mole-rats leads to behavior change by increasing care for the pups. This enhances the reactions to the cries of the pups.

In addition, these mole-rats with changed hormonal levels show more responsibility for their pup’s cries than those that never ate hormone-packed poop. Hamers (2018) claims that the mole-rats spending most of their time within their nests have higher probability of eating their poop than those living outside. As a result, they have a correspondingly higher chances of consuming the hormone and passing it to members of their colony that extends the sense of responsibility.

(A)

(B)

Figure 2: Subordinates with enhanced responses to pup cries during the postnatal period (A).

Induction of estradiol hormone during queen’s gestation and after the queen’s parturition (B) (Source: Watarai et al. 2018).

The induction of estradiol hormone in the subordinate naked mole-rats leads to behavior change and the blood estradiol concentrations among them increase through oral ingestion of the pregnant queen’s feces within their colonies (Watarai et al. 2018). This is demonstrated in Figure 2 above. As a result, a hormonal change is induced among the animals leading to alloparental pup care actions in subordinates after delivery by the females.

The figure above demonstrates that the subordinate naked mole-rats have increased parental pup care, including practices of licking, grooming moments, and warming of the queen’s pups within the colony. Estradiol concentrations among the subordinate mole-rats rose throughout the queen’s gestation period, along with a corresponding rise in their response to pup’s cries that were heightened during the queen’s postnatal stage. Mantica (2018) supports that every individual naked mole-rat has a particular role as the estradiol hormone signals assists the ready worker mole-rats in treating pups as their personal offspring. Hence, the maternal response in subordinates after induction by estradiol could be sustained during the queen’s postnatal phase through the stimulation of the pup.

The ingestion of estradiol through copography of queen’s feces enhances the reactions to the cries of the pup among naked mole-rats within their colonies (Watarai et al. 2018).

The authors postulate that oral ingestion of the pregnant queen’s feces contributes to the induction of a rise in the subordinates’ estradiol levels. Due to fact that the subordinates’ reactions to pup cries in the colonies are heightened with the help of the consumption of non-pregnant queen’s feces modified with estradiol hormone, estradiol increases care. It can be established that estradiol is the chemical that promotes naked mole-rats’ reactions to pup cries, showing a sense of good parenting among the adult females as seen in Figure 3 (Mantica 2018).

Figure 3: Illustration of part of good parenting among the naked mole-rats (Source: Mantica 2018).

Feeding subordinates with pellets containing the estradiol hormone having fecal material from the expectant females along with pellets having fecal material belonging to non-expectant females containing estradiol hormone show similar outcomes within the naked mole-rats colonies. The responses among the subordinates included behaviors that make the females be more responsible in attending to the pups whenever they make voice sounds or cries of agony. According to Watarai et al. (2018), the outcomes of the experiment the hormonal induction triggered the responses of care among the females for their pups among naked mole-rats. Within the mice populations, it was recommended that estradiol composition within the animal’s urine leads to interference with the intrauterine implantation of fertilized ova among the reproductively fertilized female naked mole-rats.

Reference List:

Hamers, L. (2018). Eating queen’s poop makes naked mole rats babysit her kids. [Online] Available at: [Accessed Dec. 27, 2018].

Henry, E. C., Dengler-Crish, C. M., & Catania, K. C. (2007). Growing out of a caste – reproduction and the making of the queen mole-rat. The Journal of Experimental Biology, 201: 261-268. doi:10.1242/jeb.02631

Mantica, G. (2018). Eating royal poop improves parenting in naked mole-rats. [Online] Available at: < https://phys.org/news/2018-10-royal-poop-parenting-naked-mole-rats.html > [Accessed Dec. 27, 2018].

Roellig, K., Drews, B., Goeritz, F., & Hildebrandt, T. B. (2011). The long gestation of the small naked mole-rat (Heterocephalus glaber Rüppell, 1842) studied with ultrasound biomicroscopy and 3D-ultrasonography. PloS one, 6(3): e17744. doi:10.1371/journal.pone.0017744

Watarai, A. et al. (2018). Responses to pup vocalizations in subordinate naked mole-rats are induced by estradiol ingested through coprophagy of queen’s feces. Proceedings of the National Academy of Sciences, 115(37): 9264-9269. Published online August 27, 2018. doi: 10.1073/pnas.1720530115.