Mammalian tumor-like organs. 1. The role of tumor-like normal organs and atypical tumor organs in the evolution of development (carcino-evo-devo)

Background Earlier I hypothesized that hereditary tumors might participate in the evolution of multicellular organisms. I formulated the hypothesis of evolution by tumor neofunctionalization, which suggested that the evolutionary role of hereditary tumors might consist in supplying evolving multicellular organisms with extra cell masses for the expression of evolutionarily novel genes and the origin of new cell types, tissues, and organs. A new theory—the carcino-evo-devo theory—has been developed based on this hypothesis. Main text My lab has confirmed several non-trivial predictions of this theory. Another non-trivial prediction is that evolutionarily new organs if they originated from hereditary tumors or tumor-like structures, should recapitulate some tumor features in their development. This paper reviews the tumor-like features of evolutionarily novel organs. It turns out that evolutionarily new organs such as the eutherian placenta, mammary gland, prostate, the infantile human brain, and hoods of goldfishes indeed have many features of tumors. I suggested calling normal organs, which have many tumor features, the tumor-like organs. Conclusion Tumor-like organs might originate from hereditary atypical tumor organs and represent the part of carcino-evo-devo relationships, i.e., coevolution of normal and neoplastic development. During subsequent evolution, tumor-like organs may lose the features of tumors and the high incidence of cancer and become normal organs without (or with almost no) tumor features.

Development and Evolution of Unisexual Flowers: A Review

The development of unisexual flowers has been described in a large number of taxa, sampling the diversity of floral phenotypes and sexual systems observed in extant angiosperms, in studies focusing on floral ontogeny, on the evo-devo of unisexuality, or on the genetic and chromosomal bases of unisexuality. We review here such developmental studies, aiming at characterizing the diversity of ontogenic pathways leading to functionally unisexual flowers. In addition, we present for the first time and in a two-dimensional morphospace a quantitative description of the developmental rate of the sexual organs in functionally unisexual flowers, in a non-exhaustive sampling of angiosperms with contrasted floral morphologies. Eventually, recommendations are provided to help plant evo-devo researchers and botanists addressing macroevolutionary and ecological issues to more precisely select the taxa, the biological material, or the developmental stages to be investigated.

Homo Paedens? Did Kids Invent the Human Species?

The evolution of development (“evo-devo”) has become a central concern in both evolu­tionary and developmental research, and human immaturity is no less a proper focus for evolutionary analysis than that of other species-if anything, it is more so. Two new books by David F. Bjorklund, a founder of evolutionary developmental psychology, summarize what we know now and propose that children invented our species. Due to the new phe­nomenon of partly heritable epigenetic modification of genes and the old one of the Bald­win Effect (by which plasticity leads to new selective forces on genes), this claim must be at least partly true. The inherent plasticity of children’s behavior, including play, accelerat­ed the evolution of humanity as instantiated in the human brain. Evolution cannot be understood without extensive reference to development, and nothing in childhood makes sense except in the light of evolution.

Genome of the bi-annual Rio Pearlfish (Nematolebias whitei), a killifish model species for Eco-Evo-Devo

The Rio Pearlfish Nematolebias whitei is a bi-annual killifish species inhabiting seasonal pools of the Rio de Janeiro region that dry twice per year. Embryos enter dormant diapause stages in the soil, waiting for the inundation of the habitat which triggers hatching and commencement of a new life cycle. This species represents a convergent, independent origin of annualism from other emerging killifish model species. While some transcriptomic datasets are available for Rio Pearlfish, thus far a sequenced genome has been unavailable. Here we present a high quality, 1.2Gb chromosome-level genome assembly, genome annotations and a comparative genomic investigation of the Rio Pearlfish as representative of a vertebrate clade that evolved environmentally-cued hatching. We show conservation of 3-D genome structure across teleost fish evolution, developmental stages, tissues and cell types. Our analysis of mobile DNA shows that Rio Pearlfish, like other annual killifishes, possesses an expanded transposable element profile with implications for rapid aging and adaptation to harsh conditions. We use the Rio Pearlfish genome to identify its hatching enzyme gene repertoire and the location of the hatching gland, a key first step in understanding the developmental genetic control of hatching. The Rio Pearlfish genome expands the comparative genomic toolkit available to study convergent origins of seasonal life histories, diapause, and rapid aging phenotypes. We present the first set of genomic resources for this emerging model organism, critical for future functional genetic and multi-omic explorations of Eco-Evo-Devo phenotypes in resilience and adaptation to extreme environments.

Evolutionary Morphogenesis of Sexual Fruiting Bodies in Basidiomycota: Toward a New Evo-Devo Synthesis

The development of sexual fruiting bodies is one of the most complex morphogenetic processes in fungi. Mycologists have long been fascinated by the morphological and developmental diversity of fruiting bodies; however, evolutionary developmental biology of fungi still lags significantly behind that of animals or plants.

Micro- and Macroscale Patterns of Petal Morphogenesis in Nigella damascena (Ranunculaceae) Revealed by Geometric Morphometrics and Cellular Analyses

Petals, the inner organs in a differentiated perianth, generally play an important role in pollinator attraction. As such they exhibit an extraordinary diversity of shapes, sizes, and colors. Being involved in pollinator attraction and reward, they are privileged targets of evolution. The corolla of the Ranunculaceae species Nigella damascena consists of elaborate nectariferous petals, made of a stalk, upper, and lower lips forming a nectar pouch, shiny pseudonectaries, and pilose ears. While the main events of petal development are properly described, a few is known about the pattern of organ size and shape covariation and the cellular dynamics during development. In this study, we investigated the relationships between morphogenesis and growth of N. damascena petals using geometric morphometrics coupled with the study of cell characteristics. First, we found that petal shape and size dynamics are allometric during development and that their covariation suggests that petal shape change dynamics are exponentially slower than growth. We then found that cell proliferation is the major driver of shape patterning during development, while petal size dynamics are mostly driven by cell expansion. Our analyses provide a quantitative basis to characterize the relationships between shape, size, and cell characteristics during the development of an elaborate floral structure. Such studies lay the ground for future evo-devo investigations of the large morphological diversity observed in nectariferous structures, in Ranunculaceae and beyond.

Interpreting ruminant specific conserved non-coding elements by developmental gene regulatory network

Biologists long recognized that the genetic information encoded in DNA leads to trait innovation via gene regulatory network (GRN) in development. Here, we generated paired expression and chromatin accessibility data during rumen and esophagus development in sheep and revealed 1,601 active ruminant-specific conserved non-coding elements (active-RSCNEs). To interpret the function of these active-RSCNEs, we developed a Conserved Non-coding Element interpretation method by gene Regulatory network (CNEReg) to define toolkit transcription factors (TTF) and model its regulation on rumen specific gene via batteries of active-RSCNEs during development. Our developmental GRN reveals 18 TTFs and 313 active-RSCNEs regulating the functional modules of the rumen and identifies OTX1, SOX21, HOXC8, SOX2, TP63, PPARG and 16 active-RSCNEs that functionally distinguish the rumen from the esophagus. We argue that CNEReg is an attractive systematic approach to integrate evo-devo concepts with omics data to understand how gene regulation evolves and shapes complex traits.

Vida y Textura Imaginal del Mundo Circundante (Umwelt)

El artículo propone una interpretación de la teoría del Umwelt formulada por Jacob von Uexküll, en la que se desarrolla la posibilidad de estudiar lo que aquí se denomina la textura imaginal del mundo circundante de los animales, en tanto material que compone sus experiencias perceptuales, afectivas y motrices. Para ello, se defiende un realismo de las imágenes a través de un dialogo entre, por un lado, el esquema sensorio-motor de la biosemiótica, la síntesis entre fisiología y medio de la ecología sensorial, los enfoques Eco evo devo y la teoría neurobiológica del self expuesta por Antonio Damasio; y, por el otro, parte de la filosofía del cine de Gilles Deleuze y de la filosofía de las imágenes de Gilbert Simondon. En este sentido, se plantea la posibilidad de una etología de la imagen-animal que sea capaz de estudiar los pliegues en movimiento de la materia bajo los signos del cine y la biología. Se hace especial énfasis en el problema de la subjetividad zoológica en tanto imagen biológica, a través de una crítica del sujeto animal en Uexküll, de raíces kantianas. Así como Uexküll propuso una imagen musical de la naturaleza que abrió su comprensión para el estudio de la conducta animal, aquí se propone activar otro tipo de potencias estéticas de su pensamiento, en aras a desplegar una imagen cinematográfica de la naturaleza que dé cuenta del estatuto etológico y ontológico de las imagenes-vivas que son los organismos.