Article
Anatomy & Morphology
Felipe Cunha, Cristian Gutierrez-Ibanez, Kelsey Racicot, Douglas R. Wylie, Andrew N. Iwaniuk
Summary: The study revealed that the variations in size and shape of the cerebellum are largely influenced by neuron numbers, rather than neuron sizes. The rate of increase in neuron numbers varied across different types of neurons, highlighting the complexity of cerebellar anatomy across species. Additionally, while the folding index was a poor predictor of surface area and Purkinje cell numbers, surface area was found to be the best predictor of Purkinje cell numbers.
BRAIN STRUCTURE & FUNCTION
(2021)
Article
Biology
Rebekah Keating Godfrey, Mira Swartzlander, Wulfila Y. Gronenberg
Summary: This study estimated total brain cell numbers for 32 species of Hymenoptera using the isotropic fractionator method, revealing ants have particularly small brains compared to bees and wasps. Small Hymenoptera tend to have proportionally larger brains and higher brain cell densities, similar to trends in most vertebrates. The study establishes the isotropic fractionator as a useful method for comparative studies of brain size evolution in insects.
PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
(2021)
Article
Genetics & Heredity
Paula Montana-Lozano, Sergio A. Balaguera-Reina, Carlos F. Prada-Quiroga
Summary: The study on reptile mitochondrial genomes reveals differences in base composition and codon usage patterns. Reptile mitochondrial genomes have low GC content with a bias towards Adenine, and the compositional asymmetry is inversely correlated with the rates of genome rearrangements. The most common codons in reptile mitochondria are shared with birds, indicating a conservation of patterns across sauropsid mitogenomes. Analysis on codon usage bias clustering and effective codon number suggests high translational efficiency and selection pressure in reptile mitochondrial genomes. The highest codon adaptation index is found in turtles, suggesting higher translational efficiency and potential metabolic adaptations.
Article
Biology
Angie S. Reyes, Amaury Bittar, Laura C. C. Avila, Catalina Botia, Natalia P. Esmeral, Natasha I. Bloch
Summary: This study investigates brain neuroanatomy in 18 wild guppy populations and finds extensive variation in brain size and brain region volumes across populations in different environments and with varying degrees of predation risk. Unlike laboratory studies, differences in allometric scaling of brain regions lead to variation in brain region proportions across populations. The study also reveals an association between sexual traits and brain size.
PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
(2022)
Article
Anatomy & Morphology
Christina N. Rogers N. Flattery, Munawwar Abdulla, Sophie A. A. Barton, Jenny M. M. Michlich, Lyudmila N. N. Trut, Anna V. V. Kukekova, Erin E. E. Hecht
Summary: The silver fox has the potential to be a powerful model for studying brain-behavior relationships. Through the Russian farm-fox experiment, different strains of the silver fox with divergent behavior have been bred, providing an excellent opportunity to investigate neuroanatomical changes underlying behavioral characteristics. The histological and MRI neuroanatomical reference of a fox from the conventional strain can be used for future studies and contribute to an understanding of fox brains and neuroanatomical variation among mammals.
BRAIN STRUCTURE & FUNCTION
(2023)
Article
Biology
Chan Lin, Henk-Jan T. Hoving, Thomas W. Cronin, Karen J. Osborn
Summary: The nervous systems of animals across Animalia share a common blueprint at the biophysical and molecular level, with strikingly conserved structure and neuronal organization in several brain regions even between diverse groups of animals. Divergent evolution to the 'neural ground pattern' has been discovered in hyperiid amphipods, with highly variable optic lobes structure and organization among closely related genera. The study demonstrates trade-offs between sensory systems and variations within the visual system in hyperiids, providing evidence of modifications in the central nervous system generating distinct combinations of visual centers in their optic lobes.
PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
(2021)
Article
Biology
Ludwik Gasiorowski, Aina Borve, Irina A. Cherneva, Andrea Orus-Alcalde, Andreas Hejnol
Summary: The brain anatomy in Spiralia can range from simple to complex structures, but the evolutionary origins of complex brains in this clade remain unclear. The study on the nemertean Lineus ruber's juveniles revealed that further neural development is mainly related to size increase rather than complexity, with distinct cell types found in both juvenile and adult cerebral organs. The expression of brain cell type markers in L. ruber suggests convergent evolution of complex brains with annelids, but with differences in gene expression patterns, potentially indicating convergent recruitment of genes into non-homologous organs or a more complex evolutionary process involving conserved and novel cell types.
Article
Anatomy & Morphology
Max S. Bennett
Summary: This article explores the milestone events in human brain evolution, introduces the concept of a "breakthrough" as a tool for explaining brain modifications and adaptive behaviors, and proposes unique hypotheses about the mechanisms of evolution.
FRONTIERS IN NEUROANATOMY
(2021)
Review
Behavioral Sciences
Fletcher J. Young, Stephen H. Montgomery
Summary: Heliconius butterflies and their Heliconiini allies have shown significant cognitive adaptations, such as an expansion of the mushroom bodies in their brains, that are related to their novel foraging behavior and superior visual memory and learning.
BEHAVIORAL ECOLOGY AND SOCIOBIOLOGY
(2023)
Article
Biology
Carmen De Miguel, Arthur Saniotis, Agata Cieslik, Maciej Henneberg
Summary: This study examined the brain/body growth in marsupials and compared it with placental mammals. The findings suggest that despite differences in morphology and cerebral organization, marsupials possess similar mental capacities as other mammals. This highlights the need for further research on the intellectual abilities of marsupials.
Review
Endocrinology & Metabolism
Claudia Pinelli, Anna Scandurra, Kazuyoshi Tsutsui, Sara Falvo, Biagio 'Aniello
Summary: This paper provides an overview of the existing knowledge on the neuroanatomical distribution of GnIH-like peptides in fish and amphibians. The study found significant differences in the distribution of GnIH-like neuropeptides among species, regardless of their evolutionary closeness. The topology of the olfactory bulbs can influence the distribution of neurons producing GnIH-like peptides. GnIH expression was detected early during development and showed an increasing trend in neuroanatomical distribution.
FRONTIERS IN NEUROENDOCRINOLOGY
(2022)
Article
Neurosciences
Uwe Homberg, Michelle Kirchner, Kevin Kowalewski, Vanessa Pitz, Michiyo Kinoshita, Martina Kern, Jutta Seyfarth
Summary: Serotonin functions as a neuromodulator in both vertebrate and invertebrate nervous systems. In insects, it affects feeding, olfactory sensitivity, aggressive behavior, and sleep homeostasis in the central complex. This study analyzed the distribution and identity of serotonin-immunoreactive neurons in various insect species, revealing taxon-specific differences in their targets and indicating distinct evolutionary changes in the composition of these neurons in the central complex.
JOURNAL OF COMPARATIVE NEUROLOGY
(2023)
Article
Ecology
Barbara Fischer, Nicole D. S. Grunstra, Eva Zaffarini, Philipp Mitteroecker
Summary: Comparing pelvic sex differences across modern humans and chimpanzees reveals a similar pattern despite differences in magnitude of pelvis shape dimorphism, suggesting that this pattern did not evolve de novo in modern humans but was present in the last common ancestor of humans and chimpanzees.
NATURE ECOLOGY & EVOLUTION
(2021)
Article
Ecology
Sara Arganda, Ignacio Arganda-Carreras, Darcy G. Gordon, Andrew P. Hoadley, Alfonso Perez-Escudero, Martin Giurfa, James F. A. Traniello
Summary: This article introduces three strategies for constructing statistical brain atlases using ants as a model taxon, and compares the accuracy of automatic and manual methods through volume similarity evaluation against human expert annotators, finding that they are equivalent.
FRONTIERS IN ECOLOGY AND EVOLUTION
(2022)
Article
Neurosciences
Dirk Jan Ardesch, Lianne H. Scholtens, Siemon C. de Lange, Lea Roumazeilles, Alexandre A. Khrapitchev, Todd M. Preuss, James K. Rilling, Rogier B. Mars, Martijn P. van den Heuvel
Summary: The study found that as brain size increases, there are restrictions on macroscopic connectivity, leading to lower overall connectedness, sparser long-range connectivity, and longer communication paths. Additionally, there were asymmetries in connectivity patterns between homologous areas across the left and right hemispheres in larger brains.