In a bird’s eyes’ view, the color red is quite meaningful. Many species use the color as a signal to attract mates or intimidate the competition, coloring their beaks and/or feathers this fiery shade. Across the board, as many birds see it, redder is better.
One Gene Two Expressions
Until now, scientists had generally accepted that DNA codes for single gene expression. This scientific discovery potentially alters our understanding of genotype and phenotype. When a bird colors its beak and/or feathers red, is this a loss or gain mutation, according to geneticists? Scientists have confirmed that the red pigment is in fact a positive mutation/evolution in the bird kingdom.
Red birds will be viewed as “more attractive” to their “normal” counterparts and are better equipped to filter and expel toxins from their system. Sounds super sexy to me. The redder, the better adapted. Natural Selection or just a simple mutation for aesthetics that just so happened to give an evolutionary benefit to the species?
The same gene that converts a bird’s nutrition to the red pigment in feathers, beaks and feet also indicates how efficient the bird detoxifies, according to research.
Red Rules: How it Works
Translation: the more red a bird is, the better potential mate it could be, because it better flushes poisons from its body.
Various species of birds, such as the zebra finch, obtain yellow pigments called carotenoids from their diet of seeds and/or insects. They then convert these pigments into the red ketocarotenoids that color their beaks and/or feathers.
Until recently, the exact location of this double-punch gene was a mystery. “Our findings fill this gap and open up many future avenues for research on the evolution and ecology of red coloration in birds,” stated Dr. Nick Mundy, from the Department of Zoology at Cambridge University in conversation with The Independent.
His research indicates that the same genes’ code for enzymes (called cytochrome P450s) play a critical role in metabolizing toxic compounds, primarily in the liver. In humans, this same enzyme affects the way people respond to pharmaceuticals.
Why Did This Gene Evolve in Birds?
Birds have a wider range of pigments in the light-sensitive photoreceptor cells of their retinas, and this adaptation allows them to see many more colors across a wider spectrum than mammals and other animals.
While still speculation, scientists believe that the ability to make red pigment may have developed for color vision in birds before it became a display tool for attracting the best mate and encourages the strongest in the species to propagate more often.
A team of researchers, including Joseph Corbo of Washington University School of Medicine in St. Louis and Geoffrey Hill of Auburn University, initially made this discovery of red pigmentation mutation thanks to canary fanciers who crossed a yellow canary with a red siskin almost 100 years ago, resulting in the animal kingdoms’ first red canary. Their search led them to a cytochrome P450 enzyme, and the rest is evolutionary history.
Where Do We Go From Here?
These newest genetic findings lead to new types of studies on the red pigmentation of birds. These findings also raise many original and interesting questions. For example, as discussed, the gene now officially identified belongs to a group of genes known to play an important role in detoxification.
Interestingly, they discovered that the “redness gene” is present in the genomes of many, if not most, bird species, not just those with red feathers, beaks or feet. So, we are now differentiating between genotype (gene instructions, i.e. genes to determine gender), phenotype (gene expression, i.e. the color of eyes in humans) and recessive/dominant genes (i.e. green versus brown eyes in humans) across species.
This understanding of this gene group could potentially lead to applications in the diagnosis and treatment of health concerns, especially involving the liver, in human beings. Of course, much more research and in vitro testing must and will be performed long before we see any new treatment developments or pharmaceuticals for people.
How This Impacts Daily Human Existence
This evolutionary scientific research has profoundly impacted the current acceptance of DNA function, gene expression and how natural selection may or may not work in the kingdom of animals. While it remains to be seen, enthusiasts await confirmation of these findings in duplicate studies by contemporaries in this field around the world. Laymen and scientists alike hope that funding will appear and the research will be done.
Perhaps a complete grasp of genetics and evolution is not meant to be completely understood by humankind. However, I, for one, am excited and intrigued to see our most intelligent and curious minds delve deeper into this subject daily. Someday soon we will have the completed the mapping of the genome for all species on planet earth. Or at least that is the future I now see on our horizon.
