February 25, 2003
From: Hans Tibboel
On a recent dive cruise in Myanmar I came across two different species of nudibranchs mating with each other. As I've never witnessed this before I was wondering if anybody else has ever noticed this same behaviour and if it will result in actual egglaying and offspring of the participating nudi's.
I guess you are not talking about the spotted and unspotted forms of Chromodoris annulata you mentioned in your last message. This question has been raised recently on the Forum when I posted Phil Slosberg's photo showing typical H. bullocki and H. apolegma mating.
In general, matings between different species are very rare, and if they occur, the eggs are either in infertile, or if offspring do occur, the offspring are infertile. There are some strange exceptions amongst the plants but on the whole, mating is considered a good indication that the partners are the same species. I realise that this argument becomes a bit circular, but organisms have usually developed good morphological and behavioural mechanisms to prevent cross-species matings.
The first question I would ask is are you sure that the two animals were actually mating, and if so, how do you know they were different species?
Re: Cross-species breeding
From: Cynthia Trowbridge, April 26, 2006
Cross-species breeding - Sea Hares
From: Jasmine Peters, March 8, 2006
From: Bill Rudman, April 9, 2003
From: Samuel K. Moore, March 8, 2003
Re: Mating behaviour
From: Hans Tibboel, March 3, 2003
Re: H. bullocki 'colour forms' mating
From: Erwin Koehler, August 6, 2002