Moo Deng, a 2-month-old female pygmy hippo who has recently become a viral internet sensation, stands next to her mother Jona, 25, at Khao Kheow Open Zoo in Chonburi province, Thailand, on Sunday. Lillian Suwanrumpha/AFP via Getty Images hide caption
True crabs are crustaceans belonging to the suborder Brachyura. The fiddler crab faced towards the camera, here, is one of those true crabs. McDonald Wildlife Photography Inc./Getty Images hide caption
Thousands of Vaux’s Swifts gather overhead as they prepare to roost for the night at Chapaman Elementary in Portland, Oregon. During the month of September, migrating swifts often use chimneys as roosts and are likely to return to the same roost year after year. Celeste Noche/for NPR hide caption
Mr. Greedy, the penguin with the most spots on his belly, is pictured at far left. Maryland Zoo hide caption
Humpback whales blow spiraling circles of bubbles to create underwater nets for their tiny prey, krill. Hunter Warick/Alaska Whale Foundation, images collected under NMFS Permit #19703 hide caption
Lilla Lanivich, 14, and her service dog, Lopez, outside their family’s home in Rochester Hills, Mich. This year’s middle school winner of the NPR Student Podcast Challenge tells how her golden retriever, Lopez, helped restore her independence. Emily Elconin for NPR hide caption
Hvaldimir pictured in Hammerfest, Norway, in 2019. He lived there for much of that year before traveling along Norway's coast and even surfacing in Sweden. Al Armiger/Alamy hide caption
From mosses to mountain lions, the temperate old-growth rainforests of the Pacific Northwest provide the complexities and conditions necessary to support high levels of biodiversity. The Northwest Forest Plan has provided protection for these ancient ecosystems over the last 30 years and has helped advance forest management in Oregon, Washington and California. Developed in response to decades of unsustainable logging practices, the plan has helped restore forest ecosystems in 17 national forests. David Herasimtschuk hide caption
Bull trout and Westslope Cutthroat Trout are among the native fish species in Western Montana that are prized by anglers and threatened by warming waters. Jonny Armstrong/U.S. Geological Survey hide caption
Los Angeles Dodger Shohei Ohtani high-fives his dog Decoy, who delivered the ceremonial first pitch before Wednesday's game against the Baltimore Orioles at Dodger Stadium in Los Angeles. Harry How/Getty Images hide caption
A white-browed sparrow weaver inspects a roost under construction, after just receiving some grass brought by another member of its group. Maria Cristina Tello-Ramos hide caption
Shells, composed mostly of invasive zebra mussels pile up at Sleeping Bear Dunes National Lakeshore in Michigan. The Nonindigenous Aquatic Nuisance Species Control and Prevention Act of 1990 and the United States Geological Survey's Nonindigenous Aquatic Species database were created in response to this mussel. corfoto/Getty Images hide caption
The central European bicolored ant, L. emarginatus, wanders around a rock in New York City. Researchers hope that people will continue uploading sightings of the so-called ManhattAnt to sites like iNaturalist so they can track the ants' movement and learn more about their behaviors. Julian F./iNaturalist hide caption
"Sphen and Magic shared a bond unlike most other penguin couples," the Sea Life Sydney Aquarium said. Sphen has died, after the male pair spent about six years together, building nests and raising chicks. Sea Life Sydney Aquarium hide caption
Arshad Nadeem of Pakistan competes during the men's javelin throw at the Olympics in Paris. He won gold, set an Olympic record — and reaped lots of prizes, including a buffalo from his father-in-law. It's all about the milk! From left: Patrick Smith/Getty Images; G A Chandio/Getty Images hide caption
Excavators unearth a 13,600-year-old mastodon skull from an Iowa creek. University of Iowa Office of the State Archaeologist hide caption
Invasive cane toads like this one have fanned out across Australia, killing numerous predators in their wake, including freshwater crocodiles. Joshua Prieto/SOPA Images/LightRocket via Getty Images hide caption
This Artibeus fruit bat feasts on sugary fruit every night but these winged mammals don’t suffer from diabetes or other metabolic problems as humans might if we were to gorge on sugar. Luis Echeverría for NPR hide caption
A Burmese python is held during a safe capture demonstration at a media event for the 2022 Florida Python Challenge on June 16, 2022, in Miami. Lynne Sladky/AP hide caption
Unlike most other ants that prefer sticking to cozy places like decaying leaves or logs, the ManhattAnt seems comfortable out on busy sidewalks. Ellen van Wilgenburg hide caption
Researchers glued cameras and tracking instruments to small pieces of neoprene, that they then glued to the fur of the sea lions Nathan Angelakis hide caption
Giant panda Xin Bao is seen in her Panda Ridge habitat at the San Diego Zoo on Wednesday, one day before the bear and a male, Yun Chuan, were due to go on display. The pandas arrived at the end of June. Sandy Huffaker/Getty Images/Getty Images North America hide caption