Cichlids and stingrays can add and subtract ‘one’ in the number space from one to five 
By V. Schluessel, N. Kreuter, I. M. Gosemann & E. Schmidt US Source: nature 3/31/2022

The numerical understanding of cichlids and stingrays was examined regarding addition and subtraction abilities within the number space of one to five. Experiments were conducted as two-alternative forced-choice experiments, using a delayed matching to sample technique.
 

On each trial, fish had to perform either an addition or subtraction, based on the presentation of two-dimensional objects in two distinct colors, with the color signaling a particular arithmetic process. Six cichlids and four stingrays successfully completed training and recognized specific colors as symbols for addition and subtraction.

 
Continue...

News Id SourceStampcountry
4526Environmental Group Gives First-Time Nod to Sustainable Salmon-Farming Methodscientific american2010-01-14US
4527Three Second Fish Memory 'Just Rubbish'; Learning And Memory 'Quite Sophisticated'Underwatertimes2010-01-14AU
4528Man catches carp the weight of Kylie Minoguetelegraph2010-01-11FR
4529Big freeze and ice is 'good for pond life'BBC News2010-01-11UK
4530New Acoustic Telemetry System Helps Explain Salmon Migration; 'A Clearer, More Complete Picture'Underwatertimes2010-01-08US
4531Giant river fish faces extinction after years of overfishingthe guardian2010-01-05US
4532Michigan balks at Obama's stance in Asian carp fightcs monitor2010-01-06US
4533Man gets house arrest for fish smugglingupi2009-12-31US
4534Sawridge Creek flood study will replace one from 1993lakesideleader2020-12-16CA
4535Michigan asks U.S. to block fish invasionUPI2009-12-21CA
4536Banned snakehead fish Rocky dies a year after being targeted by state officialsThe Post-Standard 2009-03-23US
4537Carp battle not over yetJournal Sentinel2009-11-27US
4538Biologists save fish after landslideusatoday2009-11-10US
4539It’s Official, Bass Season is Open Now in Ontario’s Zone 20fishncanada2021-02-19CA
4540Gigantic Black Crappie Sets New State Recordfishncanada2021-02-19US
4541Despite pandemic challenges, B.C. lakes stocked with millions of fishvancouversun2021-02-08CA
4542Lillooet River project a major undertaking, says new reportpiquenewsmagazine2019-04-29CA
4543The odd Hawaiianfish that Climb CliffsBBC News2021-02-10US
4544Taranaki workmates land massive fish on tiny 'undersize' boatstuff2021-02-10NZ
4545Fish Kill: Nanosilver Mutates Fish Embryosscientificamerican2009-11-17US
454695-pound catfish caught in OhioOdd News2009-11-11US
4547Farming Fish in the Skyhakaimagazine2021-02-08SG
4548Missouri man fined more than $6,000 for possessing fish over the legal limittbnewswatch2021-02-05US
4549Ask Dr. Universe: How can you tell if a fish is female or male?spokesman2021-02-07US
4550Biologist calls for judicial inquiry on salmon declinectvbc2009-10-03CA

215 216 217 181 of [218 - pages.]