Researchers have made this strange discovery while observing South African Honey Bees. In their findings, they discovered a single honey bee which has cloned itself hundred of million times over the course of thirty years. The army is possible because of the perennial cloning activity of the South African Cape honey bee (Apis Mellifera Capensis) using which they could create perfect copies of themselves.
The researchers studying this phenomenon published a paper of their findings on June 9 in the journal Proceedings of the Royal Society B.
It’s astonishing to learn that when African lowland Honey bees (Apil Mellifera Scutella) sees that they will be attacked by an army of South African Cape Honey bees they kill themselves. The whole colony gets collapsed so that the immortal army is not able to attack and grow in numbers. That too by cloning.
South African Cape honeybee queens reproduce sexually, but the workers reproduce asexually. They do this through parthenogenesis, which is how individuals reproduce, often fraught with DNA mistakes, known as re-combinations.
But in the case of South African workers bees, they were found to be nearly identical clones of their parents with little to no re-combinations in their DNA.
The Cape honey bees sneak into the hives of their lowland honeybees and make copy after copy.
Honeybee workers and other social insects have the ability to reproduce via a form of asexual reproduction called thelytokous parthenogenesis, in which females produce female offspring from unfertilized eggs.
Each time she creates offspring; the worker bee will replicate the chromosomes she received from her parents into four. Next, she takes the genetic material from all four chromosomes, reshuffles it, and creates four chromosomes with that mixed up DNA through the process called recombination. This re-shuffling guarantees that even with just one parent, future offspring will be genetically distinct.
The study has revealed something strange-female workers and, even their own queen, not reshuffling the DNA of the eggs they lay, which is unlike most animals.
This enables workers to recreate a copy of themselves (a clone) each time they reproduce. Sidelining or bypassing the DNA reshuffling process is the strangest thing the researchers have seen. According to the researchers, the reshuffling process is required to hold chromosomes together during the egg-making process. Keeping aside the reshuffling process – they had not heard of anything like this before, said the lead author Benjamin Oldroyd, a professor of behavioral genetics at the University of Sydney.
Though the Cape Honeybee follows the usual rule of social insect reproduction, Cape honeybee workers have a genetic mutation that enables them to lay eggs parthenogenetically with all of the genetic materials from four chromosomes. Now, this adds to their ability to prevent the loss of genetic diversity caused by the reshuffling process. This allows them to clone themselves whenever they like and continuously for very long years.
To understand how clones can create millions of copies and yet remain functional, Oldroyd and his team compared the genomes of cape honeybee workers with those of their queen and her offspring.
The team found that cape worker bees have evolved a mutation that prevents recombination and thus the one-third loss of the genetic material too. Workers are free to create perfect copies of themselves at will.
According to Oldroyd, this single lineage of clones is responsible for the collapse of 10% of the African Lowland honeybee colonies every year.
Now, the researchers have dug the army-raising trick of the workers through cloning. Further, they intend to know how queens can switch on to the gene that enables recombination and how the workers can switch it off. They also want to investigate the African Lowland hives parasitized by Cape bee workers, to figure out what triggers the hive collapse.
Who knows where else the cloning is rampant, as this discovery!