Cannibalism Of The Young Allows Individual Fish To Specialize 
SW Source: Underwatertimes 5/23/2007

If you go fishing for Arctic char you may end up catching distinctly different-looking individuals although they were all caught in the same lake. Similarly, whitefish, threespine stickleback, and some sunfishes also display quite discrete groups living in the same lakes but utilizing different food resources in order to survive. The phenomenon is called resource polymorphism and has been observed and documented as early as in the 18th century, but has continued to receive a lot of scientific interest since it gives us a chance to study ongoing evolution. However, not all species display resource polymorphism, and naturally, in order to gain deeper understanding of evolutionary facilitators, the question arises: Why do some species display resource polymorphism, whereas other don't?
 

In this study, a team of European researchers combines literature data and advanced ecological theory in order to look for species-specific life history patterns explaining the presence/absence of resource polymorphism in fish. Interestingly and not at all obvious, the study suggests that early cannibalism, which is found in all species displaying resource polymorphism, is a promoting factor. However, incorporating recently explored and presented population dynamic theory, based upon the population's size distribution and the effect of the individual's size on its relative competitiveness, a logic explanation is given. The effect of early cannibalism is twofold. First, it stabilizes the variation in the number of individuals over time, which in turn increases the benefit of specializing on any resource since the risk of being dependent on a vanishing resource decreases. Second, an early disappearance of small newborn individuals increases the abundance of their prey due to decreased consumption from the small ones, hence increasing the benefit for larger individuals to specialize on this specific prey (typically zooplankton). The team now plans to do new modeling exercises and practical experiments in order to further explore the suggested hypothesis.

 
Char, Arctic Continue...

News Id SourceStampcountry
1151The lady whos looking to help Libya fulfil its true aquaculture potentialthefishsite2023-12-11LY
1152На Черном море все чаще говорят о лавракеohotniki2023-12-07RU
1153CA Academy of Sciences Steinhart Aquarium turns 100abc7news2023-11-29US
1154Environmental change threatens Japans cormorant fishing legacyjapantimes2023-11-30JP
1155Wyoming teen recognized as one of the state’s youngest Ultimate Anglerslocalnews82023-11-30US
1156Equipment failure kills 100,000 salmon worth $5M at advanced land-based fish farm in N.S.CBC News2023-11-29CA
1157Heres what Minnesotas new lake littering law means for ice fishingbringmethenews2023-12-01US
1158In retirement, Fargo angler is fishing lure craftsmanechopress2023-12-12US
1159Cooke lands $4.7 grant for True North Salmon processing plantthefishsite2023-12-08CA
1160В начале ледового сезонаohotniki2023-12-05RU
1161Cave creature — with transparent fins — found swimming in China.miamiherald2023-12-01CN
1162Study points to concurrent marine heat waves as culprit in Western Alaskaalaskabeacon2023-12-02US
1163Too little, too late: the desperate search for cod babiestheguardian2023-11-27UK
1164Transgender teacher Becky Lee Birtwhistle Hodges chosen for England Ladies angling teamkentonline2018-06-02UK
1165Mediterranean sea fish strengthened amidst Gaza Warjpost2023-11-29EU
1166Lake Volta tilapia farmers await government relief funds following floodingthefishsite2023-12-08GA
1167Gavin Newsom Advances Water Tunnel Project Amid Opposition From Environmental GroupsAssociated Press2023-12-08US
1168Theres no such thing as too much ice fishing gearechopress2023-12-09US
1169Wild salmon conservation group raises concerns about herring killsmsn2023-12-06CA
1170SAIC secures funding for seven fish health projectsthefishsite2023-12-07US
1171Advocates Say a Mexican Startup Is Illegally Selling a Health DrinkAssociated Press2023-12-07MX
1172Aucklanders ignore safety warnings, continuing to fish in the polluted Waitematā harbourRNZ2023-12-06NZ
1173Five Fishermen net $10,500 fine after catching 348 fish in Hauraki Gulfnzherald2023-10-08NZ
1174Major New Zealand salmon producer shuts farms as warming waters cause mass die-offstheguardian2022-05-26NZ
1175Overfishing and climate change impacts on New Zealand's fish populations were hiddenphys2023-09-21NZ

219 220 221 46 of [222 - pages.]