Linnaeus and the invisible world

Linnaeus expressed his fascination for microscopy in his work Mundum Invisibilem 1767 (the invisible world), which was one of the very first attempts to bring light and order to the microscopic discoveries of the time. Linnaeus wrote about his only microscopic experiment in the same publication. He wanted to know where to place the fungi in his grand 'Systema Naturae', but misinterpreted the results of the experiment completely. This is perhaps one of Linnaeus' greatest and least known mistakes, but one that somehow boosted development anyway.
We took the original microscope models used by Linnaeus, took photos, and compared them with images obtained with modern instruments. Our experiments revealed several new findings, and let us understand why Linnaeus made his mistake. One other finding is that Linnaeus must have used the most modern and advanced compound microscope of his time, a large Cuff microscope in his experiment. Only two large microscopes by Cuff were available in Sweden by the time. A large Cuff microscope was found in Sweden lately. This microscope is probably the actual instrument that Linnaeus used.     

Gregarines Found in the Honey Bee Apis mellifera Linnaeus in Venezuela.

SUMMARY. Gregarines were found for the first time in the honey bee Apis mellifera L. in Venezuela. The parasites attacked the inner wall of the ventriculus of the adult bees, causing heavy losses in apiculture in October 1954 and June 1955. The disease produced was called gregarina disease of the honey bee (in Spanish "gregarinosis de la abeja").     

Comparative anatomy of the intestine of Cyprinus carpio Linnaeus 1758 and Salmo trutta Linnaeus 1758

The anatomy of carp and trout was compared by means of anatomical dissection and frozen cross-sections. This enabled exact topographical localization and hence also the determination of differences in the position of individual intestinal segments. The elaboration of a suitable nomenclature was considered to be an important working measure for the facilitation of interspecific comparison.     

Caryospora cobrae n. sp. from the Indian Cobra Naja naja Linnaeus

Oocysts of Caryospora cobrae n. sp. were isolated from an Indian cobra, Naja naja Linnaeus from West Bengal, India. The sporulated oocysts were spherical to subspherical, 16.5-19.5 times 16.5-18.0 μm, and had a micropyle but lacked a polar granule and oocysl residuum. The sporocysts were piriform, measuring 12.0-16.5 times 9.0?12.8 μm; a Stieda body and sporocyst residuum were present.     

Ciliate protozoa in the rumen of Brazilian water buffalo, Bubalus bubalis Linnaeus.

Total numbers and distribution of genera, subgenera and species were determined for the ciliate protozoa in rumen contents of 4 Brazilian water buffalo Bubalus bubalis Linnaeus. The fauna of one animal, housed in close proximity to European and zebu-type cattle, differed considerably from that of the remaining animals, which were somewhat isolated on a large ranch. Several of the protozoan species observed in the semi-isolated animals were first described in rumen contents from humped Indian cattle, and their subsequent occurrence in other hosts and geographic locations has been limited or absent. In all, 49 different species of protozoa were found, 8 of which have not been previously described. Three of the new species belong to the genus Entodinium: E. ciculum sp. n., E. spinonucleatum sp. n. and E. triangulum sp. n.; 4 to Diplodinium (Ostracodinium): D. (O.) brazili sp. n., D. (O.) esalqum sp. n., D. (O.) nucleolobum sp. n., and D. (O.) tiete sp. n.; and one to Diplodinium (Eudiplodinium): D. (E.) bubalus sp. n.     

Inferring the population structure and demographic history of the tick, Amblyomma americanum Linnaeus.

A hierarchial population genetic study was conducted on 703 individual Amblyomma americanum from nine populations in Georgia, U.S.A. Populations were sampled from the Coastal Plain, midland Piedmont region, and the upper Piedmont region. Twenty-nine distinct haplotypes were found. A minimum spanning tree was constructed that indicated these haplotypes comprised two lineages, the root of which was distinctly star-like. The majority of the variation found was among ticks within each population, indicating high amounts of gene flow and little genetic differentiation between the three regions. An overall F(ST) value of 0.006 supported the lack of genetic structuring between collection sites in Georgia. Mantel regression analysis revealed no isolation by distance. Signatures of population expansion were detected in the shapes of the mismatch distribution and tests of neutrality. The absence of genetic differentiation combined with the rejection of the null model of isolation by distance may indicate recent range expansion in Georgia or insufficient time to reach an equilibrium where genetic drift may have affected allele frequencies. Alternatively, the high degree of panmixia found within A. americanum in Georgia may be due to bird-mediated dispersal of ticks increasing the genetic similarity between geographically separated populations.     

Toxoplasma ranae sp. n. from the Leopard Frog Rana pipiens Linnaeus*

SYNOPSIS. Toxoplasma ranae sp. n. is described from the brain of a leopard frog, Rana pipiens, probably from Mexico. Its pseudocysts were 72(55-106) × 48(29-70) μm in fixed sections. They contained an average of ～ 4,000 slightly curved elongate zoites measuring 4–5 × 0.5 μm, with a central, spherical, vesicular nucleus.     

Mimicry and the evolution of premating isolation in Heliconius melpomene Linnaeus

Ecological divergence can cause speciation if adaptive traits have pleiotropic effects on mate choice. In Heliconius butterflies, mimetic patterns play a role in mate detection between sister species, as well as signalling to predators. Here we show that male butterflies from four recently diverged parapatric populations of Heliconius melpomene are more likely to approach and court their own colour patterns as compared with those of other races. A few exceptions, where males were more attracted to patterns other than their own, suggest that some mimetic patterns are sub-optimal in mate choice. Genotype frequencies in hybrid zones between races of H. melpomene suggest that mating is random, so reinforcement is unlikely to have played a role in intra-specific divergence. In summary, co-evolved divergence of colour pattern and mate preference occurs rapidly and is likely the first step in Heliconius speciation.     

Linnaeus in 20th century Sweden

JONSELL, B., 1992. Linnaeus in 20th century Sweden. An account is presented of Linnaeus as a national monument in present-day Sweden, the current popular romantic view, scholarly studies on Linnaeus, the natural history tradition in Sweden, the role of Linnaeus in trade and tourism, and the literary tradition.     

Linnaeus,animals and man*

Linnaeus is often undervalued as a zoologist. His importance lies not only in the introduction of binomial nomenclature and his Systema Naturae. As a systematist he divided the insects into the groups, Coleoptera, Hemiptera, Lepidoptera, Neuroptera, Hymenoptera, Diptera and Aptera. His programme, as expressed in his Methodus in Systema Naturae (1st ed.) is astounding in its biological manysidedness. He was before his time in many respects: he wrote and lectured upon bird migration, biological control of insects with their parasites or predators, protective mimicry, the struggle by all organisms for survival, contagious diseases as well as fermentation due to small living particles. He was the first to call attention to the close relationship between man and the anthropoid apes.     

Diel locomotor activity pattern of juvenile Limulus polyphemus Linnaeus.

Ten juvenile Limulus polyphemus, tested individually for 3-day periods in electronic shuttleboxes, exhibited a nocturnal activity pattern; activity was four times as great at Night as during the Day.