Los vertebrados usados en protocolos experimentales son reconocidos como sintientes, lo cual favorece su consideración desde la zooética, su protección en la legislación nacional e internacional, así como la salva- guarda de su bienestar. En consecuencia, se ha recurrido a otros modelos in vivo como los animales invertebrados para realizar investigación. Salvo casos particulares, los invertebrados no cuentan con la protección legal ni existe preocupación por su bienestar, en tanto que se les consideraba no sintientes. Por lo tanto, se realizó (...) una revisión de artículos científicos (de 1997 a 2022) para examinar la sintiencia entre los grupos Mollusca, Arthropoda y Nematoda, phyla ampliamente utilizados como modelos experimentales. Se encontraron dieciocho artículos que constataron un cierto grado de sintiencia en estos phyla, por lo que se propone su inclu- sión en la reflexión zooética. Este texto constituye un primer esfuerzo para procurar el bienestar de estos individuos utilizados en procedimien- tos experimentales. (shrink)

Paleoneuranatomy is an emerging subfield of paleontological research with great potential for the study of evolution. However, the interpretation of fossilized nervous tissues is a difficult task and presently lacks a rigorous methodology. We critically review here cases of neural tissue preservation reported in Cambrian arthropods, following a set of fundamental paleontological criteria for their recognition. These criteria are based on a variety of taphonomic parameters and account for morphoanatomical complexity. Application of these criteria shows that firm evidence for fossilized (...) nervous tissues is less abundant and detailed than previously reported, and we synthesize here evidence that has stronger support. We argue that the vascular system, and in particular its lacunae, may be central to the understanding of many of the fossilized peri‐intestinal features known across Cambrian arthropods. In conclusion, our results suggest the need for caution in the interpretation of evidence for fossilized neural tissue, which will increase the accuracy of evolutionary scenarios. Also see the video abstract here: https://youtu.be/2_JlQepRTb0. (shrink)

Chelicerates (scorpions, horseshoe crabs, spiders, mites and ticks) are the second largest group of arthropods and are of immense importance for fundamental and applied science. They occupy a basal phylogenetic position within the phylum Arthropoda, and are of crucial significance for understanding the evolution of various arthropod lineages. Chelicerates are vectors of human diseases, such as ticks, and major agricultural pests, such as spider mites, thus this group is also of importance for both medicine and agriculture. The developmental genetics (...) of chelicerates is poorly understood and a challenge for the future progress for many aspects of chelicerate biology is the development of a model organism for this group. Toward this end, we are developing a chelicerate genetic model: the two‐spotted spider mite Tetranychus urticae. T. urticae has the smallest genome of any arthropod determined so far (75 Mbp, 60% of the size of the Drosophila genome), undergoes rapid development and is easy to maintain in the laboratory. These features make T. urticae a promising reference organism for the economically important, poorly studied and species‐rich chelicerate lineage. BioEssays 29:489–496, 2007. © 2007 Wiley Periodicals, Inc. (shrink)

Metaseiulus occidentalis is a representative of an important family of mites (Arthropoda: Chelicerata: Acari: Phytoseiidae) that are effective predators of pest mites in agricultural crops around the world. Like many arthropods, this mite contains multiple genomes, including the genomes of several microbial symbionts as well as its own mitochondrial and nuclear genomes. The mitochondrial genome is “mitey” large at 25 kb, due to duplication and triplication of genes. By contrast, the nuclear genome is “mitey” small at 88 Mb. This (...) mite has a parahaploid genetic system, tolerates inbreeding, and has a haploid chromosome number of 3. This predator was genetically improved for use in agriculture by developing strains that lacked the ability to overwinter in diapause or were resistant to multiple pesticides, and can be genetically modified using recombinant DNA methods. Sequencing the nuclear genome would provide useful insights that could enhance genetic improvement programs that would result in improved pest management, could provide genes needed to resolve the evolutionary relationships of this family, and could serve as a model for understanding the evolution and genetics of chelicerate arthropod predators. (shrink)

Eyesight is practically a main organ of senses for man orienting in the world. But it is also a result of evolutional development of nature from 600 to 450 mln. years according to evolutional scale and still it preserves its stable contradictory inner structure. The genesis of eyesight has been reconstructed in Arthropoda type. It was made possible by using a philosophical approach, namely, by considering this process from the dualism point of view. Two Laurence's concepts were used as (...) basic interrelated categories. They are intranspecific and interspecific aggressiveness. Development of the two interrelated opposites results in the formation of a new kind – eyesight (Hegelian not Marx’s), typical for all succeeding kinds of animals. The eye has become a unity consisting of on- and off-type ganglionic cells, that percept both fixed end non-fixed objects simultaneously. The two eyes of higher animals and man allow to orient in the world, and depending on outside conditions, they can fully enough demonstrate one of the stable contradictory inner tendencies. This is just one of the directions in studying philosophy of nature. (shrink)