How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
Citations since 2017
268 Research Items
After a long time in animal behaviour research (causes for the evolution of different social structures), I drifted more and more into marine biology and these days do little more than faunistics and zoogeography of the Atlantic marine fauna. peterwirtz2004(at)yahoo.com
As mitochondria are inherited in a matrilinear way, an animal hybrid contains the mitochondrial DNA of its 'mother species'. Of 80 studies that analysed the mitochondrial DNA of at least five hybrid individuals, 50 showed that all hybrids contained the mitochondrial DNA of only one of the two parental species, indicating either mating of females of...
In a much quoted study, BORNSTEIN & BORNSTEIN (1976) showed that the walking speed of pedestrians is positively correlated with the size of the city. They interpreted the higher walking speed of people in larger cities as a psychological response to stimulatory overload. We also found a positive correlation between walking speed and city size. In a...
There is sometimes a significant bias in the sex ratio of fish caught by longline. Usually, more females than males are caught. The possible reasons for unequal sex ratios in longline catches are listed and discussed. One sex could be more common in the area where the fishery takes place because there really is an unequal sex ratio in the populatio...
While eating, Homo sapiens frequently look up and visually scan their environment. As in many bird and mammal species studied, the frequency of looking up was negatively correlated with group size. Average duration of scanning the environment also correlated negatively with group size. At all group sizes studied (1–5), females spent less time scann...
The Azores, Madeira, Selvagens, Canary Islands and Cabo Verde are commonly united under the term "Macaronesia". This study investigates the coherency and validity of Macaronesia as a biogeographic unit using six marine groups with very different dispersal abilities: coastal fishes, echinoderms, gastropod molluscs, brachyuran decapod crustaceans, po...
Abstract: Fincrawling is a unique, recognizable behaviour pattern exhibited by many flatfishes (order Pleuronectiformes), whereby the fish uses the fin rays of the dorsal and anal fins to walk over the substratum. The distribution of this behaviour among flatfishes indicates it appeared early in the phylogeny of the Pleuronectiformes. Fincrawling i...
Added pictures of a red colour morph of Tripterygion delaisi, of reproductive colours of Parablennius parvicornis, and others.
First record of Serranus inexpectatus and S. papilionaceus for the country.
The clingfish Diplecogaster roseioculus sp. nov. is described on the basis of a single specimen from São Tomé Island, eastern Atlantic Ocean. The species is small, not exceeding 16 mm total length; it is characterized by having 7 dorsal-fin rays and 7 anal-fin rays, 29 pectoral-fin rays, 17 caudal-fin rays; gill rakers on 3rd arch 12; head width 4....
Malacoctenus africanus was encountered in the Bijagos archipelago.
Territorial Sicydium bustamatei male displaying and chasing first a Sicydium brevifile female and then a small S. bustamantei male. River Io Grande, Sao Tome island. Funding: “LittleFish-STP: São Tome and Príncipe little fish threatened - a big opportunity to unravel this fishery resource in tropical islands” (nº 541718158; Aga Khan, Network for D...
High density of feeding Sicydium brevifile in Io Grande River, Sao Tome Island. At 30 seconds a male and a female S. bustamantei can be seen. Funding: “LittleFish-STP: São Tome and Príncipe little fish threatened - a big opportunity to unravel this fishery resource in tropical islands” (nº 541718158; Aga Khan, Network for Development and Portugues...
The Starry Weever (Trachinus radiatus) is recorded for the first time in the Madeira archipelago in the Northeast Atlantic Ocean. Baited Remote Underwater Video (BRUV) surveys conducted between June and August 2022 showed the presence of T. radiatus around the island of Deserta Grande. The species is likely to be present in other areas of the archi...
Added Cirrhipathes sp., Stichopathes setacea, and a second undescribed Tanacetipathes species. There are still more species in caves and dark places which need identification.
corrected genus name Hoplometopus and family name Callichiridae; added photo juvenile H. antillensis .
We have already published a pictorial catalogue of the Perophoridae. Here are the other two families of the order Phelebobranchia at Madeira.
Abstract: The common eulimid snail currently called Parvioris mariajoae Ortea & Moro 2021 is a parasite of the holothurian Isostichopus cf. badionotus at the Cabo Verde Islands. The species also occurs at São Tomé and Príncipe and at Ascension Island. I suspect it should be assigned to a different genus.
We have already published pictorial catalogues of the shallow-water Clavelinidae, Polyclinidae, and Polycitoridae of Madeira. Here are the remaining two families of the order Aplousobranchia from Madeira.
There appears to be a correlation between colour intensity and latitude in some shallow water marine species, for instance a starfish being dark red in the tropics and pale/pink at its northern edge of distribution. Does anybody know a reference about this which I can quote ?
The "Instructions for authors" of some journals are now four times (!) as long as they were 40 years ago. Many of the demands made in them are totally unnecessary, and many of them I consider unreasonable. The demand of an Orcid number is a recent example (voluntary ok, compulsory no).
In my opinion, journals should accept articles in any format for submission (e.g. authors in the references not in capitals, year of publication not in brackets, journal name not in bold print, ... or whatever other demands that journal makes). Adapting to the format of that particular journal should be necessary only after acceptance. To re-write the publication list for a different journal (after, for instance, a reviewer has rejected the paper and demanded more data even though they are not necessary for the point made) is one of the most stupid wastes of my lifetime I know...
Which journals in the area of zoology are the least demanding as regards formatting ?
Peter Wirtz (email@example.com).
In a nice article on a mimicry system
it is stated that model and mimic have to co-occur.
I believe this is wrong.
Imagine a migratory bird that encounters the model in Africa and the mimic in Europe (or vice versa). Model and mimic do not have to co-occur. They only have to be experienced by the same individual.
Does anybody know such cases ?
When, many years ago, the journal Animal Behaviour started to demand ethics statements for articles submitted to them, I objected to it for the following reasons:
1) It is morally wrong to demand that the innocent should prove their innocence.
2) The bad guys will simply lie.
And therefore ethic statements are a useless addition to all those many many submission requirements that already have no other effect than to waste time and energy (on ORCID number is one of the latest and particularly inane examples that comes to mind).
A recent article on the molecular phylogeny of Octopus has now added an additional twist to the story. The authors blithely state
“No live animals were experimented on during this study. Tissue samples were obtained via donation from existing museum or university collections, or taken from whole deceased animals that were purchased from fish markets.”
This is quite simply untrue. When I collected a tissue sample from an Octopus in a tide pool at Ascension Island, I grabbed one of its tentacles and quickly cut a small piece of the tip off it. I think that this corresponds to a small would the animal might obtain in the course of its life and I have only a moderately bad conscience about it. So how come the authors made this wrong statement ? They do not know because they received the sample via a third person ! And also: how were those other samples collected ? Is it ok if somebody else tortures animals and deposits them in a museum and then you use them for a genetic study ?
So here is another reason why ethic statements in journal are a farce: they force authors to make statements about things they do not know.