Nav: Home

Fruit flies help to shed light on the evolution of metabolism

January 03, 2019

Diet choice of animal species is highly variable. Some are specialists feeding only on one food source, such as a sugar-rich fruit or protein-rich meat. Other species, like humans, are generalists that can feed on different kinds of food sources.

Because of these differences, animal species ingest different amounts of macronutrients, like carbohydrates and amino acids. It is conceivable that the metabolism has to match the diet choice of each species. However, we understand poorly the evolution of animal metabolism - what are the underlying genetic changes and how these changes define the optimal nutrient composition for a given species.

The research group led by Associate Professor Ville Hietakangas at the University of Helsinki have studied the evolution of metabolism by using two very closely related fruit fly species.

The first one of them is a generalist, Drosophila simulans, which feeds on varying fruits and vegetables, which typically contain a high amount of sugars. The second one is Drosophila sechellia, which has specialized to feed on one fruit, Noni, Morinda citrifolia, which has low sugar content.

"We found pretty dramatic metabolic differences between these species. D. sechellia larvae, that are not exposed on sugar in nature, were not able to grow when placed on a sugar-rich diet, while D. simulans had no problems handling dietary sugar," explains Hietakangas.

The close relatedness of the fruit fly species allowed the scientist interbreed the species, to make hybrids that were largely genetically like D. sechellia, but contained those genomic regions of D. simulans that were needed for sugar tolerance.

"The ability to analyze hybrid animals was the key advantage of our study. This way we could not only rely on correlating the findings but were able to identify genetic changes that were causally important. We also could tell that sugar tolerance comes with a cost. D. simulans and the sugar tolerant hybrids survived poorly on a low nutrient diet. This suggests that D. sechellia has evolved to survive on a low nutrient environment, which has required rewiring the metabolism in a way that has made feeding on high sugar impossible," says Hietakangas.

This study opens up many interesting questions, also related to humans. In the future, it will be interesting to explore whether human populations that have different dietary histories, for example experiencing extremely limited nutrition for many generations, may respond differently to modern diets rich in sugars.
-end-


University of Helsinki

Related Evolution Articles:

Insect evolution: Insect evolution
Scientists at Ludwig-Maximilians-Universitaet (LMU) in Munich have shown that the incidence of midge and fly larvae in amber is far higher than previously thought.
Evolution of aesthetic dentistry
One of the main goals of dental treatment is to mimic teeth and design smiles in the most natural and aesthetic manner, based on the individual and specific needs of the patient.
An evolution in the understanding of evolution
In an open-source research paper, a UVA Engineering professor and her former Ph.D. student share a new, more accurate method for modeling evolutionary change.
Chemical evolution -- One-pot wonder
Before life, there was RNA: Scientists at Ludwig-Maximilians-Universitaet (LMU) in Munich show how the four different letters of this genetic alphabet could be created from simple precursor molecules on early Earth -- under the same environmental conditions.
Catching evolution in the act
Researchers have produced some of the first evidence that shows that artificial selection and natural selection act on the same genes, a hypothesis predicted by Charles Darwin in 1859.
Guppies teach us why evolution happens
New study on guppies shows that animals evolve in response the the environment they create in the absence of predators, rather than in response to the risk of being eaten.
Undercover evolution
Our individuality is encrypted in our DNA, but it is deeper than expected.
Evolution designed by parasites
In 'Invisible Designers: Brain Evolution Through the Lens of Parasite Manipulation,' published in the September 2019 issue of The Quarterly Review of Biology, Marco Del Giudice explores an overlooked aspect of the relationship between parasites and their hosts by systematically discussing the ways in which parasitic behavior manipulation may encourage the evolution of mechanisms in the host's nervous and endocrine systems.
Tracing the evolution of vision
The function of the visual photopigment rhodopsin and its action in the retina to facilitate vision is well understood.
Directed evolution comes to plants
Accelerating plant evolution with CRISPR paves the way for breeders to engineer new crop varieties.
More Evolution News and Evolution Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

Risk
Why do we revere risk-takers, even when their actions terrify us? Why are some better at taking risks than others? This hour, TED speakers explore the alluring, dangerous, and calculated sides of risk. Guests include professional rock climber Alex Honnold, economist Mariana Mazzucato, psychology researcher Kashfia Rahman, structural engineer and bridge designer Ian Firth, and risk intelligence expert Dylan Evans.
Now Playing: Science for the People

#540 Specialize? Or Generalize?
Ever been called a "jack of all trades, master of none"? The world loves to elevate specialists, people who drill deep into a single topic. Those people are great. But there's a place for generalists too, argues David Epstein. Jacks of all trades are often more successful than specialists. And he's got science to back it up. We talk with Epstein about his latest book, "Range: Why Generalists Triumph in a Specialized World".
Now Playing: Radiolab

Dolly Parton's America: Neon Moss
Today on Radiolab, we're bringing you the fourth episode of Jad's special series, Dolly Parton's America. In this episode, Jad goes back up the mountain to visit Dolly's actual Tennessee mountain home, where she tells stories about her first trips out of the holler. Back on the mountaintop, standing under the rain by the Little Pigeon River, the trip triggers memories of Jad's first visit to his father's childhood home, and opens the gateway to dizzying stories of music and migration. Support Radiolab today at Radiolab.org/donate.