Age vs. Theoretical Growth Limit

[Fujisawas Sake]

Hello All!

Does anyone know about the theoretical growth limit of Architeuthis or Mesonchyoteuthis? Do cephs in general grow to a limit, then stop growth (a sharp curve that reaches a limit) or do they continue to grow throughout their lifetime (a sharp curve that levels off but continues to rise at a greatly deceased slope)?

Sushi and Sake,

John

 

[Architeuthoceras]

John,
I believe they continue to grow at a steady rate until they reach sexual maturity. That is how they concluded that some fossil cephalopods are pathologic giants, being neutered by parisites, they never reach sexual maturity and continue to grow. Obviously the only growth rate they have to go on are from living cephalopods.

 

[Fujisawas Sake]

Thanks Kevin!

Where did you read/hear this?

John

 

[Architeuthoceras]

Manger, Meeks, and Stephan, 1999, Pathologic Gigantism in Middle Carboniferous Cephalopods, Southern Midcontinent, United States, in: Advancing Research on Living and Fossil Cephalopods, edited by Oloriz and Rodriquez-Tovar, Kluwer Academic/Plenum Publishers

 

[Fujisawas Sake]

Thanks again, Kevin!

As a followup....

There seems to be no link between ectothermy/endothermy and determinant growth, so I was wondering if there was any known physiological or genotypic determining growth factors in cephs?

For example, mammals can suffer atrophy after prolonged periods of inactivity, while more activity changes the physiology of the organism to adapt to higher output (why we become stronger after periods of exercise). However, most land-based ectotherms don't show this pattern... They tend not to atrophy as easily, but also don't adapt to exercise as such. Is there any physiologic or genotypic limiting factor in inverts, (cephs would be nice to know) that would regulate growth ?


John

 

[Jean]

Not sure John, but I do know that the growth curve for a ceph does not reach an asymptote. Also growth is different for male and female (at least in some species)


if you wnt to see some curves for Nototodarus let me know & I will email them to you...can't figure out how to attach them on here (they're in word).

Cheers

J

 

[Fujisawas Sake]

Thanks Jean!

My e-mail addy is on my profile.

John

 

[Phil]

John,
I believe they continue to grow at a steady rate until they reach sexual maturity. That is how they concluded that some fossil cephalopods are pathologic giants, being neutered by parisites, they never reach sexual maturity and continue to grow. Obviously the only growth rate they have to go on are from living cephalopods.

John,

Here is a good example of such a condition in a giant nautiloid:

Shell-Shock: Three University Of Arkansas Students Find World's Longest Nautiloid Fossil

Good images of the same find are available here:

http://advancement.uark.edu/news/NEWS_ARCHIVES/JAN03/Cephalopod.html

Apologies if you have seen this before.

Phil

 

[Fujisawas Sake]

A better question is are there any known inverts that show indeterminant growth?

 

[Steve O'Shea]

Here are a ton of papers that might be of interest!

Jackson, G.D., McGrath-Steer, B. Wotherspoon, S. & Hobday, A.J. (2003) Variation in age, growth and maturity in the Australian arrow squid Nototodarus gouldi over time and space – what is the pattern? Mar. Ecol. Prog. Ser. 264: 57-71

Jackson, G.D. & G. Pecl. (2003) The dynamics of the summer spawning population of the loliginid squid Sepioteuthis australis in Tasmania, Australia – a conveyor belt of cohorts ICES J. Mar. Sci. 60: 290-296.

Jackson, G.D. & M.L. Domeier (2003) The effects of an extraordinary El niño/La niña event on the size and growth of the squid Loligo opalescens off Southern California. Mar. Biol. 142: 925-935.

Jackson, G.D. & J.W. Forsythe (2002) Statolith age validation and growth of Loligo plei (Cephalopoda: Loliginidae) in the Gulf of Mexico during spring/summer. J. Mar. Biol Ass. U.K. 82: 677-678.

Jackson G.D. & N.A. Moltschaniwskyj (2002) Spatial and temporal variation in growth rates and maturity in the Indo-Pacific squid Sepioteuthis lessoniana (Cephalopoda: loliginidae) Mar.Biol. 140: 747-754.

Jackson G.D. & R.K. O’Dor (2001) Time, space and the ecophysiology of squid growth, life in the fast lane. Vie et Milieu. 51: 205-215.

Jackson G.D. & N.A. Moltschaniwskyj (2001). Temporal variation in growth rates and reproductive parameters in the small near-shore tropical squid, Loliolus noctiluca; is cooler better? Mar. Ecol. Prog. Ser. 218: 167-177.

Jackson, G.D.& N.A. Moltschaniwskyj (2001) The influence of ration level on growth and statolith increment width of the tropical squid Sepioteuthis lessoniana (Cephalopoda: Loliginidae): an experimental approach. Mar. Biol. 138:819-825

Moltschaniwskyj, N.A. & G.D. Jackson (2000) Growth and proximal composition as a function of feeding history in juvenile cephalopods. J. Mar. Biol. Ecol. 253: 229-241.

Jackson, G.D., R.A. Alford & J.H. Choat (2000) Can squid populations be analysed using standard fishery length-based techniques? ICES J. Mar. Sci. 57: 948-954.

Jackson, G.D. & N.A. Moltschaniwskyj (1999) Tests for precision in squid statolith age estimates of Photololigo (Cephalopoda: Loliginidae) off Queensland, Australia. ICES J. Mar. Sci. 56: 221-227.

Jackson, G.D. (1998) Research into the life history of Loligo opalescens: where to from here? Calif. Coop. Fish. Invst. Repts. 39:101-107.

Jackson, G.D. & V.A. Wadley (1998) Age, growth and reproduction of the tropical squid Nototodarus hawaiiensis (Cephalopoda: Ommastrephidae) off the North West Slope of Australia. Fish. Bull. 96: 779-787.

Jackson, G.D., J.W. Forsythe, R.F. Hixon & R.T. Hanlon (1997) Age, growth and maturation of Lolliguncula brevis (Cephalopoda: loliginidae) in the Northwestern Gulf of Mexico with a comparison of length-frequency vs. statolith age analysis. Can. J. Fish. Aquat. Sci. 54: 2907-2919.

Jackson, G.D., N.G. Buxton & M.J.A. George (1997) Beak length analysis of Moroteuthis ingens (Cephalopoda: Onychoteuthidae) from the Falkland Islands region of the Patagonian Shelf. J. Mar. Biol. Assoc. U.K. 77: 1235-1238.

Jackson, G.D. (1997) Age, growth and maturation of the deepwater squid Moroteuthis ingens (Cephalopoda: Onychoteuthidae) in New Zealand waters. Polar Biol. 17: 268-274.

Jackson, G.D. & J. Yeatman (1996) Variation in size and age-at-maturity in Photololigo from the North West Shelf of Australia. Fish. Bull. 94: 59-65.

Jackson, G.D. (1995) Seasonal influences on statolith growth in the tropical near-shore loliginid squid Loligo chinensis (Cephalopoda: Loliginidae) off Townsville, North Queensland, Australia. Fish. Bull. 93: 747-751.

Jackson, G.D. & C.C. Lu. (1994) The statolith microstructure of seven species of Antarctic squid captured in Prydz Bay, Antarctica. Antarctic Science 6: 195-200.

Jackson, G.D. (1994) Application and future potential of statolith increment analysis in squids and sepioids. Can. J. Fish. Aquat. Sci. 51: 2612-2625.

Jackson, G.D. (1994) Statolith age estimates of the loliginid squid Loligo opalescens (Mollusca: Cephalopoda), corroboration with culture data. Bull. Mar. Sci. 54: 554-557.

Jackson, G. D. (1993) Growth zones within the statolith microstructure of the deepwater squid Moroteuthis ingens (Cephalopoda: Onychoteuthidae): evidence for a habitat shift? Can. J. Fish. Aquat. Sci. 50: 2366-2374.

Alford, R.A. & G.D. Jackson (1993) Do cephalopods and larvae of other taxa grow asymptotically. Am. Nat. 141: 717-728.

Jackson, G.D. & J.H. Choat (1992) Growth in tropical cephalopods; an analysis based on statolith microstructures. Can. J. Fish. Aquat. Sci. 49: 218-228.

Jackson, G.D., C.C. Lu, & M. Dunning (1991) Microstructural growth rings in the statoliths of the giant squid Architeuthis. Veliger 34: 331-334.

Jackson, G.D. (1990) The use of tetracycline staining techniques to determine statolith growth ring periodicity in the tropical loliginid squids Loliolus noctiluca and Loligo chinensis. Veliger 33: 395-399.

Jackson, G.D. (1990) Age and growth of the tropical near-shore loliginid squid Sepioteuthis lessoniana determined from statolith growth ring analysis. Fish. Bull. 88: 113-118.

Jackson, G.D. (1989) The use of statolith microstructures to analyse life-history events in the small tropical cephalopod Idiosepius pygmaeus. Fish. Bull. 87:265-272.

 

[Jean]

hmmmmmm there's a definite trend in authorship of those papers!



J