New Research Adds to the Story of Penguins
2022-07-24
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1Researchers recently offered the most complete examination yet of the history of penguins.
2Penguins are short-legged flightless seabirds that mainly live in the southern half of the world.
3The researchers studied the genomes of the 20 living penguin species and subspecies.
4With more than three quarters of known penguin species no longer existing,
5the researchers also included in their study 50 fossil species using skeletal data.
6The researchers said penguins came from a common ancestor shared with a group of seabirds that includes albatrosses and petrels.
7Penguins first developed the ability to dive, like a puffin, and then lost the ability to fly as they adapted to water.
8The earliest-known penguin is called Waimanu manneringi, from New Zealand.
9It is believed to have lived 61 million years ago.
10Daniel Ksepka of the Bruce Museum in Greenwich, Connecticut, is the co-writer of the study that was published in Nature Communications.
11"We know penguins evolved from flying birds, but that happened over 60 million years ago and we need to look to the fossil record to piece together where, when and how that happened," he said.
12Ksepka noted that penguins are appealing animals.
13He added that they "are ridiculously charming creatures.
14They love, they fight, they steal, and because of their funny upright posture it's really easy to imagine them having all the same motivations as people."
15Motivation is a term that means a cause or reason for doing something.
16The study proposes that changes in world temperatures and in major ocean currents have been important drivers of penguin evolution.
17Penguins live mainly in the Southern Hemisphere.
18The Galapagos penguin is the only one found north of the equator.
19The University of Copenhagen's Theresa Cole was the study's lead writer.
20Cole said the research found a number of genes likely involved in physical changes known as adaptations.
21Such adaptations include gene mutations that shift the way penguins see the world.
22Penguins' vision is more sensitive toward the blue end of the color spectrum.
23Blue light goes more deeply into the ocean than light at the red end of the spectrum.
24Genes that help birds detect salty and sour tastes are active in penguins.
25But genes that help detect bitter, sweet and savory tastes are inactivated.
26Those may no longer be needed as penguins find food in cold, salty water and usually swallow prey including fish, shrimp and squid whole.
27Penguins show changes in their wing bones and a reduction of their flight feathers.
28Penguins also have reduced air spaces in the skeleton and the ability to store more oxygen in their muscles for long dives.
29Penguins were once much larger than today's species.
30One ancient species, Kumimanu biceae, lived in New Zealand between 55 and 60 million years ago and stood about 1.8 meters tall.
31The largest modern species, the emperor penguin, is about one meter tall.
32I'm John Russell.
1Researchers recently offered the most complete examination yet of the history of penguins. 2Penguins are short-legged flightless seabirds that mainly live in the southern half of the world. 3The researchers studied the genomes of the 20 living penguin species and subspecies. With more than three quarters of known penguin species no longer existing, the researchers also included in their study 50 fossil species using skeletal data. 4The researchers said penguins came from a common ancestor shared with a group of seabirds that includes albatrosses and petrels. Penguins first developed the ability to dive, like a puffin, and then lost the ability to fly as they adapted to water. 5The earliest-known penguin is called Waimanu manneringi, from New Zealand. It is believed to have lived 61 million years ago. 6Daniel Ksepka of the Bruce Museum in Greenwich, Connecticut, is the co-writer of the study that was published in Nature Communications. 7"We know penguins evolved from flying birds, but that happened over 60 million years ago and we need to look to the fossil record to piece together where, when and how that happened," he said. 8Ksepka noted that penguins are appealing animals. He added that they "are ridiculously charming creatures. They love, they fight, they steal, and because of their funny upright posture it's really easy to imagine them having all the same motivations as people." 9Motivation is a term that means a cause or reason for doing something. 10The study proposes that changes in world temperatures and in major ocean currents have been important drivers of penguin evolution. 11Penguins live mainly in the Southern Hemisphere. The Galapagos penguin is the only one found north of the equator. 12The University of Copenhagen's Theresa Cole was the study's lead writer. Cole said the research found a number of genes likely involved in physical changes known as adaptations. 13Such adaptations include gene mutations that shift the way penguins see the world. Penguins' vision is more sensitive toward the blue end of the color spectrum. Blue light goes more deeply into the ocean than light at the red end of the spectrum. 14Genes that help birds detect salty and sour tastes are active in penguins. But genes that help detect bitter, sweet and savory tastes are inactivated. Those may no longer be needed as penguins find food in cold, salty water and usually swallow prey including fish, shrimp and squid whole. 15Penguins show changes in their wing bones and a reduction of their flight feathers. Penguins also have reduced air spaces in the skeleton and the ability to store more oxygen in their muscles for long dives. 16Penguins were once much larger than today's species. One ancient species, Kumimanu biceae, lived in New Zealand between 55 and 60 million years ago and stood about 1.8 meters tall. The largest modern species, the emperor penguin, is about one meter tall. 17I'm John Russell. 18Will Dunham reported on this story for Reuters. John Russell adapted it for VOA Learning English. 19________________________________________________________________ 20Words in This Story 21species - n. biology : a group of animals or plants that are similar and can produce young animals or plants 22fossil - n. something (such as a leaf, skeleton, or footprint) that is from a plant or animal which lived in ancient times 23adapt - v. to change (something) so that it functions better or is better suited for a purpose 24ridiculously - adv. to an extreme extent 25charming - adj. very pleasing or appealing : full of charm 26posture - n. the way in which your body is positioned when you are sitting or standing 27spectrum - n. a continuum of color formed when a beam of white light is dispersed 28______________________________________________________________ 29What do you think of penguins? We want to hear from you. 30We have a new comment system. Here is how it works: 31Write your comment in the box. 32Under the box, you can see four images for social media accounts. They are for Disqus, Facebook, Twitter and Google. 33Click on one image and a box appears. Enter the login for your social media account. Or you may create one on the Disqus system. It is the blue circle with "D" on it. It is free. 34Each time you return to comment on the Learning English site, you can use your account and see your comments and replies to them. Our comment policy is here.