Mole rats that live in hives | Sunday Observer

Mole rats that live in hives

25 September, 2022

London-based Evolutionary ecologist, Chris Faulkes has done research on naked mole-rats for three decades and says that “They truly are unique”.

Mole rats are a pink, almost hairless rodent that live in hills they construct out of the earth in eastern Africa - Kenya, Ethiopia, Djibouti and Somalia.

These surprisingly long-lived animals (a lifespan of up to 30 years, while your average house rat lives for 3 years only) and are one of two truly eusocial mammals, the other is the Damaraland Mole Rat in Southern Africa.

They live in large colonies where only one female and maybe a couple of males breed. The majority spend their lives as ‘workers’. This is very similar to some insects like wasps, ants or bees.

Professor. Faulkes started working on them in the 1990s , when the scientific community had less information than now. Few dialects of Kenyan Luhya call it Imbuco, the Samburu call it Itturumet or blind one and Somalis call it Fadhaanfadh. However, the word fuco and its variants have spread across Southeastern Africa for both ‘haired’ and naked mole rats.

Local views about it vary across Africa. Mole-rats are believed to be a bad omen in Zimbabwe, but in neighbouring Zambia, some eat them - there are no naked mole-rats here, so these are other ‘haired’ mole-rat species obviously.

Some Luhya clans believe that if a naked mole-rat has arrived, the queen is demanding half your crop. Somali people have a belief that they can make camels sick. It is also rumoured that witch doctors use them to make hexes in black magic.

The honey-gathering Yaaku tribe are also familiar with them. Faulkes says that “most locals haven’t heard of them, but a few are very adept at catching them and helped us with the research.”

They spend most of their time excavating and foraging in burrows but emerge to search for seeds or other vegetation to eat. Colonies also have their own ‘dialects’, dictated by the queen and this changes whenever a new queen emerges - it is also a mechanism to deter intruders.

Colonies can host 60-300 individuals, with 70 being a bit more average sized. Damaraland mole rats however live in colonies of 10 on average and up to 40 individuals maximum. There is a queen and maybe a male or a couple more which breed.

The rest are unable to breed, but when the queen dies, a non-breeding female takes the place as the new queen, so we think there is a mechanism that a queen uses to turn off reproductive ability. Some serve on guard duty as ‘soldiers’. They have also been observed kidnapping babies from neighbouring colonies to raise as their own.

Zoologist Nigel Bennett says that “Damaraland Mole Rats have smaller colonies than naked mole rats of around 10 animals per group. The queens in both suppress the reproductive ability of subordinates, however in the naked mole rat, there is more physical aggression by the queen towards subordinates (shoving).”

“One reason why we call these two species ‘eusocial’ is because only an estimated 1percent naked mole rats reproduce; in Damaraland mole rats it is 10 percent” he said. In that aspect, other mole rat species are more likely to breed as adults. Cooperative brood care and overlapping generations are other components of this definition. Bennet explained that “where there is more rainfall, the colonies are smaller as they become more dispersed.”

According to zoologist Markus Zöttl from Sweden’s Linnaeus University “A very striking new discovery is that after they disperse, a single female Damaralands can survive very well while alone in a burrow before building a new colony. So, they don’t necessarily need the group for survival as we thought for a long time.” He said “The young stay for 1-5- 2 years as helpers. Females later leave and try to start a new group. Males will try to find single females or try to invade other groups to overpower and take over from resident males.”

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