Scientists learn about the ‘ridiculously lovely’ history of penguins
Penguins first evolved the ability to dive, like a puffin, and subsequently lost the ability to fly as they adapted to an aquatic realm, becoming excellent swimmers and divers.
One of the wonders of the animal kingdom is how penguins evolved from their flying seabird ancestors into the flightless inhabitants of aquatic settings from the chilly Antarctica to the balmy Galapagos Islands.
The history of penguins going back to their beginnings more than 60 million years ago was examined in detail for the first time by researchers on Tuesday. This included identifying a group of genes important in adaptations related to underwater vision, long dives, body temperature regulation, diet, and body size.
The 20 current species and subspecies of penguins had their genomes sequenced. The researchers also included 50 prehistoric species using skeleton data in their analysis because more than three-quarters of the known penguin species are now extinct.
According to the researchers, penguins descended from a common ancestor with petrels and albatrosses, a group of seabirds. Like puffins, penguins first developed the capacity to dive, and when they acclimated to an aquatic environment, they lost the ability to fly. Instead, they became skilled swimmers and divers.
The earliest-known penguin, named Waimanu manneringi, comes from New Zealand and dates to 61 million years ago, or around 5 million years after the great extinction that wiped off the dinosaurs.
Bird palaeontologist Daniel Ksepka of the Bruce Museum in Greenwich, Connecticut, and co-author of the study that was published in the journal Nature said, “To me, penguins are a perfect example of a major evolutionary transition, like the evolution of an aquatic lifestyle in whales or flight in bats.”
“We are aware that penguins descended from flying birds more than 60 million years ago, but to determine exactly when, when, and how this transition had place, we must consult the fossil record. Penguins are also quite endearing animals. It’s really simple to imagine them having all the same motives as people because of their strange upright stance, and they love, fight, and steal, according to Ksepka.
The study demonstrated how fluctuations in the main ocean currents and variations in global temperature have been significant forces in penguin evolution.
The traces of population crashes and booms left in each penguin species’ genome allowed researchers to assess how their populations have changed over the past 250,000 years, according to Ksepka. Penguins were significantly impacted by the waxing and waning of ice sheets, and species that are vulnerable to declining sea ice may suffer significantly from future global warming.
Additionally, it was shown that penguins had the lowest evolutionary rates of any bird species to date. The majority of penguin species, including the Adelie penguin near Antarctica’s beaches, are found in the Southern Hemisphere. The only penguin found north of the equator is the Galapagos penguin.
Theresa Cole, a postdoctoral researcher at the University of Copenhagen and the study’s first author, said the investigation identified a number of genes that are probably responsible for particular physiological adaptations in penguins.
Their vision is shifted toward the blue end of the colour spectrum due to gene abnormalities that they have. Since blue light penetrates the ocean more deeply than light at the red end of the spectrum, this characteristic aided in improving vision for underwater, low-light acuity.
In penguins, genes that aid in the detection of sour and salty tastes are activated. However, inactivated genes prevent people from tasting bitter, sweet, or savoury flavours. Given that penguins hunt in cold, saline water and often eat prey like fish, shrimp, and squid whole, those may no longer be required.
Penguins’ wing bones flatten and harden, and their flight feathers are reduced to small structures that aid in the transformation of wings into flippers. In order to improve diving efficiency, they also decreased the air holes in the skeleton, thickened the bone walls, and developed the capacity to store more oxygen in their muscles for prolonged dives.
In the past, penguins were much larger than they are now. One species, Kumimanu biceae, was about 6 feet (1.8 metres) tall and lived in New Zealand between 55 and 60 million years ago. The emperor penguin, the tallest species still in existence, stands roughly 3 feet (1 metres) tall.
One of the wonders of the animal kingdom is how penguins evolved from their flying seabird ancestors into the flightless inhabitants of aquatic settings from the chilly Antarctica to the balmy Galapagos Islands.
The history of penguins going back to their beginnings more than 60 million years ago was examined in detail for the first time by researchers on Tuesday. This included identifying a group of genes important in adaptations related to underwater vision, long dives, body temperature regulation, diet, and body size.
The 20 current species and subspecies of penguins had their genomes sequenced. The researchers also included 50 prehistoric species using skeleton data in their analysis because more than three-quarters of the known penguin species are now extinct.
According to the researchers, penguins descended from a common ancestor with petrels and albatrosses, a group of seabirds. Like puffins, penguins first developed the capacity to dive, and when they acclimated to an aquatic environment, they lost the ability to fly. Instead, they became skilled swimmers and divers.
The earliest-known penguin, named Waimanu manneringi, comes from New Zealand and dates to 61 million years ago, or around 5 million years after the great extinction that wiped off the dinosaurs.
Bird palaeontologist Daniel Ksepka of the Bruce Museum in Greenwich, Connecticut, and co-author of the study that was published in the journal Nature said, “To me, penguins are a perfect example of a major evolutionary transition, like the evolution of an aquatic lifestyle in whales or flight in bats.”
“We are aware that penguins descended from flying birds more than 60 million years ago, but to determine exactly when, when, and how this transition had place, we must consult the fossil record. Penguins are also quite endearing animals. It’s really simple to imagine them having all the same motives as people because of their strange upright stance, and they love, fight, and steal, according to Ksepka.
The study demonstrated how fluctuations in the main ocean currents and variations in global temperature have been significant forces in penguin evolution.
The traces of population crashes and booms left in each penguin species’ genome allowed researchers to assess how their populations have changed over the past 250,000 years, according to Ksepka. Penguins were significantly impacted by the waxing and waning of ice sheets, and species that are vulnerable to declining sea ice may suffer significantly from future global warming.
Additionally, it was shown that penguins had the lowest evolutionary rates of any bird species to date. The majority of penguin species, including the Adelie penguin near Antarctica’s beaches, are found in the Southern Hemisphere. The only penguin found north of the equator is the Galapagos penguin.
Theresa Cole, a postdoctoral researcher at the University of Copenhagen and the study’s first author, said the investigation identified a number of genes that are probably responsible for particular physiological adaptations in penguins.
Their vision is shifted toward the blue end of the colour spectrum due to gene abnormalities that they have. Since blue light penetrates the ocean more deeply than light at the red end of the spectrum, this characteristic aided in improving vision for underwater, low-light acuity.
In penguins, genes that aid in the detection of sour and salty tastes are activated. However, inactivated genes prevent people from tasting bitter, sweet, or savoury flavours. Given that penguins hunt in cold, saline water and often eat prey like fish, shrimp, and squid whole, those may no longer be required.
Penguins’ wing bones flatten and harden, and their flight feathers are reduced to small structures that aid in the transformation of wings into flippers. In order to improve diving efficiency, they also decreased the air holes in the skeleton, thickened the bone walls, and developed the capacity to store more oxygen in their muscles for prolonged dives.
In the past, penguins were much larger than they are now. One species, Kumimanu biceae, was about 6 feet (1.8 metres) tall and lived in New Zealand between 55 and 60 million years ago. The emperor penguin, the tallest species still in existence, stands roughly 3 feet (1 metres) tall.
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