evolution

Taken during the 2021 ‘desierto florido‘ event near Caldera, Chile. The purple background is due to Cistanthe longiscapa, the object of this study. Credit: Oven Pérez-Nates

Diversity in flower color and patterning is even greater for pollinators.

The Atacama desert, which stretches for nearly 1,600 kilometers along the western coast of South America’s cone, is the driest place on the planet. Some of the weather stations there have never recorded any rain in all of their years of operation. However, it’s far from being lifeless; numerous species that are unique to this area exist here and have adapted to its harsh environment. And, every five to ten years, from September to mid-November, the Atacama presents one of the most stunning sights of the natural world: the ‘desierto florido‘ (literally, ‘blooming desert’). These mass blooms, one of which is presently taking place in the northern Atacama following considerable rainfall earlier this year, frequently draw international media attention.

However, what physiological and evolutionary mechanisms allow for the enormous variety of flower colors, shapes, and visual patterns seen in desiertos floridos? And how do pollinators, mainly hymenopterans like solitary wasps and bees in the Atacama, who are the beneficiaries of this visual spectacle, perceive all this variation? This is the topic of recent research published in the journal Frontiers in Ecology and Evolution.

evolution

The ‘desierto florido‘ event in Sep-Nov 2021 near the city of Caldera, Chile, as viewed by satellite. The mass bloom is dominated by purple pussypaws Cistanthe longiscapa (family Montiaceae). Credit: European Union, Copernicus Sentinel-2 imagery

“Our aim was to shed light on the ecological and evolutionary mechanisms that cause biological diversity in extreme environments like the Atacama desert,” said first author Dr. Jaime Martínez-Harms, a researcher at the Institute of Agricultural Research in La Cruz, Chile.

“Here we show that flowers of the pussypaw Cistanthe longiscapa, a representative species for desiertos floridos in the Atacama desert, are highly variable in the color and patterns they present to pollinators. This variability probably results from different so-called ‘betalain’ pigments in the flower petals.”

Model species

Martnez-Harms and colleagues investigated a desierto florido event in late 2021 in the northern Chilean city of Caldera. A dominant species was C. longiscapa (family Montiaceae), an annual plant up to 20 cm high, which bloomed in two distinct patches tens of km across. These patches consisted of – to human eyes – uniformly purple and yellow flowers. Between them grew numerous intermediate (ie, reddish, pinkish, and white) flowers of the same species, strongly suggesting that the purple and yellow morphs are heritable variants that can interbreed.

evolution

Purple pussypaw Cistanthe longiscapa (family Montiaceae), the focus of this study. Credit: Oven Pérez-Nates

Visualizing flowers as insects see them

Insects, with their compound eyes and different sensitivities, see the world very differently than we do. For example, most hymenopterans have three types of photoreceptors, which are maximally sensitive to UV, blue, and green. Martínez-Harms et al. used cameras sensitive to visible light and UV and spectrometers to measure the reflection, absorption, and transmission of different wavelengths by the petals of a total of 110 purple, yellow, red, pink, and white C. longiscapa flowers. This enabled them to produce composite images of these variants as seen by their many species of pollinators.

Diversity hidden from human eyes

The results show that just within this single plant species, the diversity perceptible to pollinators was greater than to us. For example, hymenopterans, just like us, can easily distinguish between red, purple, white, and yellow variants. But they can also distinguish between flowers with a high versus a low UV reflection among yellow and purple flowers. A UV ‘bullseye pattern’ at the heart of some flowers, which guides pollinators to the nectar and pollen, is invisible to us.

evolution

Taken during the 2021 ‘desierto florido‘ near Caldera, Chile. The purple flowers are Cistanthe longiscapa, the object of this study. Credit: Oven Pérez-Nates

An exception are the UV-reflecting pink and reddish C. longiscapa, which are quite distinct to human eyes, but probably appear similar to hymenopterans.

This visual diversity of C. longiscapa flowers is probably mainly due to differences between betalains – yellow, orange, and purple pigments that are a typical trait of the plant order Caryophyllales to which the pussypaws belong. Betalains don’t just give colors to flowers: they also protect from drought, salt stress, and damage from reactive oxygen radicals under environmental stress – traits highly beneficial in deserts.

Pollinators drive the selection of new variants

The authors hypothesized that the observed standing diversity within C. longiscapa flowers is driven by differences in the sensitivity and preference for different colors and patterns across many species of pollinators: an evolutionary experiment going on right now, which mostly escapes our eyesight.

“The great variation in flower color within C. longiscapa can be explained if different species of pollinating insects, through their preference for particular flower colors and patterns, could cause these variants to become reproductively isolated from other individuals of the same plant species. This ongoing process could ultimately lead to the origin of new races or species,” said Martínez-Harms.

“In our next studies, we will further investigate the chemical identity and the biological synthesis pathways of betalains and other flower pigments, as well as their relationship to traits such as the scents produced by the flowers. This should help us to understand their role in shaping the interactions between plants and their pollinators, and in the plants’ tolerance to biotic and abiotic stressors under fluctuating climate conditions,” said Martínez-Harms.

Reference: “Mechanisms of flower coloring and eco-evolutionary implications of massive blooming events in the Atacama Desert” by Jaime Martínez-Harms, Pablo C. Guerrero, María José Martínez-Harms, Nicolás Poblete, Katalina González, Doekele G. Stavenga and Misha Vorobyev, 21 October 2022, Frontiers in Ecology and Evolution.
DOI: 10.3389/fevo.2022.957318

The study was funded by the AFOSR/EOARD, the FONDECYT, the ANID-Millennium Science Initiative Program, and ANID/BASAL.

TECH NEWS RELATED

A nuclear-powered rocket could take astronauts to Mars in just 45 days

NASA’s manned mission to Mars would take seven months with the current technology we have for rockets. However, a nuclear-powered spacecraft could make that trek in just 45 days, according to news shared by the space agency. The design, which has been in the works in some fashion for ...

View more: A nuclear-powered rocket could take astronauts to Mars in just 45 days

Hubble’s stunning Butterfly Nebula image shows how our Sun will die

The sun will die, eventually. Like any star, the one at the center of our solar system is not meant to live forever. Eventually, it will use up all of the nuclear fuel in its core and explode, becoming a shell of what it once was. Now, Hubble’s various images ...

View more: Hubble’s stunning Butterfly Nebula image shows how our Sun will die

Hubble spotted a black hole snacking on the donut-shaped remains of a star

NASA’s Hubble space telescope spotted a black hole munching on the donut-shaped remains of a star in a galaxy nearly 300 million light-years away. The telescope was unable to capture any images of the donut-shaped remains, as the galaxy is too far away. But it was able to capture ...

View more: Hubble spotted a black hole snacking on the donut-shaped remains of a star

Scientists in Canada detected an 8 billion-year-old radio signal in a distant galaxy

Scientists have detected a record-breaking radio signal from atomic hydrogen in a very distant galaxy. The galaxy that the signal originated from is believed to have come from a galaxy at redshift z=1.29. Because of the galaxy’s immense distance, the emission line had shifted to a 48 cm line from ...

View more: Scientists in Canada detected an 8 billion-year-old radio signal in a distant galaxy

Green Bank Telescope captured the most detailed images of the Moon ever taken from Earth

Astronomers have taken the most detailed image of the Moon ever taken from Earth, and it was done with a device that uses less power than a household microwave oven. The Green Bank Telescope, which uses a low-power radar transmitter to capture data, along with the Very Long Baseline Array, ...

View more: Green Bank Telescope captured the most detailed images of the Moon ever taken from Earth

Polar Ignite 3 fitness watch review: Excellent battery, not great performance

While the likes of the Apple Watch may dominate the field in Apple-land, there’s still plenty of room for alternatives, regardless of smartphone platform. Many of these competitors, like Garmin and Polar, focus largely on health and fitness — and the latest of these is the new Polar Ignite 3. ...

View more: Polar Ignite 3 fitness watch review: Excellent battery, not great performance

Scientists think Jupiter’s moon Io may be home to alien life

The volcanic moon, which orbits the gas giant Jupiter, has long been written off as a possible home for alien life, as its extreme temperature and lava-covered surface make it wholly inhabitable. But, now scientists say that the volcanic moon could house life deep underground, perhaps even in the lava ...

View more: Scientists think Jupiter’s moon Io may be home to alien life

Nreal Air smart glasses review: A lightweight augmented reality experience

Mixed reality products are well and truly on the way. While the likes of the Meta Quest Pro perhaps isn’t the best bang for your buck, the Quest 2 is still a great product that makes virtual reality a whole lot more fun. But Meta isn’t the only player around ...

View more: Nreal Air smart glasses review: A lightweight augmented reality experience

Physicists have used entanglement to ‘stretch’ the uncertainty principle, improving quantum measurements

NASA already unveiled a successor to James Webb that will search for life on alien planets

Astronomers reveal the most detailed radio image yet of the Milky Way’s galactic plane

Revolutionary SBSP tech will try to beam solar power to Earth from space

Why does Nepal’s aviation industry have safety issues? An expert explains

Study claims the Milky Way is missing almost half of its regular matter

On a tiny Australian island, snakes feasting on seabirds evolved huge jaws in a surprisingly short time

They say we know more about the Moon than about the deep sea. They’re wrong

Astronomers found a rare star that was eclipsed for 7 years

A nearby galaxy merger may be hiding dual black holes that are 750 light-years apart

NASA’s Lunar Flashlight probe hits trouble on journey to the moon

AI is being used to figure out animal languages, forget Midjourney

OTHER TECH NEWS

Top Car News Car News