Investigating “Humanity”

The American Biology Teacher, Год журнала: 2025, Номер 87(2), С. 103 - 112

Опубликована: Фев. 1, 2025

Although the central principles of evolution by natural selection can feel both abstruse and culturally fraught for learners all ages, evolutionary logic is at core biological science: once students have a solid understanding evolution, they better understand everything else in biology. We present here hands-on experience, coupled with intentional questioning strategies, that inspires to use high-level thinking begin asking excellent questions about what we know how it. This activity leverages skull replicas humans, chimps, hominins tap into young people’s curiosity where come from it means be person—fundamental topics inquiry people just coming their own identities. Along way, are also exposed important data create arguments archaeological record currently tell us story like came be.

Язык: Английский

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Selection, evolution and persistence of paleoecological systems

Frontiers in Earth Science, Год журнала: 2025, Номер 13

Опубликована: Фев. 13, 2025

The Phanerozoic fossil record can be organized as a nested set of persistent paleoecological units, ranging from paleocommunities to Sepkoski’s Evolutionary Faunas. This paper argues that the basis for ecological persistence on geological timescales is rooted in robustness communities, is, resistance and resilience communities when perturbed by environment. Here I present Ecological Functional Networks Hypothesis (EFNH) proposes networks species functions, or (EFNs), underlie stasis persistence, EFNs are both subject selection evolve. An EFN varies if composition hence functional structures its constituent vary, may differ each other based those numerical representation, biogeographic distribution. That variation acting community composition, determines an differential among multiple EFNs. Selection pressures turn exert top-down influence evolution extinction. Evidence presented establish reality record, example, persist even changes, EFNs, which apparent during after episodes severe biotic turnover such mass extinctions. Finally, tests suggested make EFNH falsifiable, including testing correlation between emergent traits using models paleocommunity dynamics examine relationship persistence. should applied broadly throughout diverse environments. part growing body hypotheses address selection, non-reproducing systems, ecosystems entire biospheres, addresses concepts timescales.

Язык: Английский

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Estimation of maximum body size in fossil species: A case study using Tyrannosaurus rex

Ecology and Evolution, Год журнала: 2024, Номер 14(7)

Опубликована: Июль 1, 2024

Among extant species, the ability to sample extremes of body size-one most useful predictors an individual's ecology-is highly unlikely. This improbability is further exaggerated when sampling already incomplete fossil record. We quantify likelihood uppermost limits size in record using

Язык: Английский

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The macroecology of Mesozoic dinosaurs

Biology Letters, Год журнала: 2024, Номер 20(11)

Опубликована: Ноя. 1, 2024

Dinosaurs thrived for over 160 million years in Mesozoic ecosystems, displaying diverse ecological and evolutionary adaptations. Their ecology was shaped by large-scale climatic biogeographic changes, calling a ‘deep-time’ macroecological investigation. These factors include temperature fluctuations the break up of Pangaea, influencing species richness, diversity history. Recent improvements dinosaur fossil record have enabled studies their responses to tectonic, geographic shifts. Trends diversity, body size reproductive traits can now be analysed using quantitative approaches like phylogenetic comparative methods, machine learning Bayesian inference. patterns sometimes align with, but also deviate from, first-order rules (e.g. species–area relationship, latitudinal biodiversity gradient, Bergmann’s rule). Accurate reconstructions palaeobiodiversity niche partitioning require ongoing taxonomic revisions detailed anatomical descriptions. Interdisciplinary research combining sedimentology, geochemistry palaeoclimatology helps uncover environmental conditions driving Fieldwork under-sampled regions, particularly at extremes, is crucial understanding spatial heterogeneity ecosystems across planet. Open science initiatives online databases play key role advancing this field, enriching our deep-time processes, offering new insights into macroecology its broader implications.

Язык: Английский

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The Tyrant Lizard King, Queen and Emperor: Multiple Lines of Morphological and Stratigraphic Evidence Support Subtle Evolution and Probable Speciation Within the North American Genus Tyrannosaurus

Evolutionary Biology, Год журнала: 2022, Номер 49(2), С. 156 - 179

Опубликована: Март 1, 2022

Язык: Английский

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Osteohistological description of ostrich and emu long bones, with comments on markers of growth

Journal of Anatomy, Год журнала: 2022, Номер 241(2), С. 518 - 526

Опубликована: Апрель 12, 2022

Abstract Ostriches and emus are among the largest extant birds frequently used as modern analogs for growth dynamics of non‐avian theropod dinosaurs. These ratites quickly reach adult size in under 1 year, such do not typically exhibit annually deposited marks. Growth marks, commonly classified annuli or lines arrested (LAGs), represent reduced halted osteogenesis, respectively, their presence demonstrates varying degrees developmental plasticity. marks have yet been reported from ostriches emus, prompting authors to suggest that they lost plasticity required deposit them. Here we observe hind limb bone histology three captive juvenile one ostrich. Two typical but third emu, a 4.5‐month‐old juvenile, exhibits regional arc avascular tissue, which interpret mark. As this mark is present other two same cohort it co‐occurs with contralateral broken fibula, variable biomechanical load potential cause. The ostrich complete ring avascular, hypermineralized sparse, flattened osteocyte lacunae. We identify an annulus slowing growth. In absence lacking animal's life history, timing cause ostrich's unclear. Even so, these findings demonstrate both taxa retain ancestral temporarily slow also discuss challenges identifying using incomplete population data sets partial cortical sampling.

Язык: Английский

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Demographic interpretation of colossal theropod footprints discoveries from Imilchil (Mid-Jurassic, Central High Atlas, Morocco)

Journal of African Earth Sciences, Год журнала: 2022, Номер 193, С. 104595 - 104595

Опубликована: Май 24, 2022

Among the footprints found in Imilchil (Central High Atlas, Morocco) are two large ichnites that we characterize as "colossal" to distinguish them from "giant" theropod usage of other authors. These discoveries add scarce record very footprints, and contribute knowledge spatial-temporal distribution such colossal footprints. We classify sites with dinosaur tracks by their geographic location age Temporal Geographical Circumscriptions (TGCs) lead separation nine TGCs containing tracks. analyzed total content described relate footprint populations size. This analysis, which extends Middle Jurassic Upper Cretaceous, distributes geographically a limited (non-random) way. As consequence above, hypothesze may be zonal possibly due latitude, climate or geographical barriers. localized different according geological period.

Язык: Английский

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“Dragons” on the landscape: Modeling the abundance of large carnivorous dinosaurs of the Upper Jurassic Morrison Formation (USA) and the Upper Cretaceous Dinosaur Park Formation (Canada)

The Anatomical Record, Год журнала: 2022, Номер 306(7), С. 1669 - 1696

Опубликована: Июль 11, 2022

Abstract Counts of the number skeletal specimens “adult” megaherbivores and large theropods from Morrison Dinosaur Park formations—if not biased by taphonomic artifacts—suggest that big meat‐eaters were more abundant, relative to plant‐eaters, than one would expect on basis abundance carnivores herbivores in modern mammalian faunas. Models megaherbivore population density (number individuals per square kilometer) attempt take into account ecosystem productivity, size structure populations, individual energy requirements, when combined with values theropod/megaherbivore ratio, suggest may have been abundant landscape estimates extrapolated versus body mass relationship carnivores. meat production populations requirements herbivore productivity insufficient support associated theropods, unless production/biomass ratio was substantially higher, and/or theropod requirement markedly lower, expectations based mammals. Alternatively, or addition both these other factors, likely included dinosaurs as significant components their diet.

Язык: Английский

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Coexistence, Energy, and Trophic Cascade in a Three-Level Food Chain Integrating Body Sizes

Frontiers in Ecology and Evolution, Год журнала: 2022, Номер 10

Опубликована: Июнь 21, 2022

Predation is a biological interaction that influences demographic patterns by modifying community structure. In the current ecological crisis, there need to better understand conditions of coexistence between predators, prey and their resources. The body size considered key feature explain community-scale phenomena, energetic, evolutionary constraints. This raises question how species directly or indirectly affects enable coexistence. Considering above, we conducted theoretical study implements Rosenzweig-MacArthur type model, which represents three-level chain integrates sizes includes Holling I functional response. this characterize through size-dependent net reproductive rates. Our results suggest consumer strongly affect size-density relations energy requirements. We obtain negative relationship density intermediate consumers discuss equivalence rule. Furthermore, larger predators have more significant impact on intensity trophic cascade than smaller predators. Finally, potential extensions applications our modeling approach.

Язык: Английский

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A mathematical model to calculate the population of Mammuthus columbi (Mammalia, Proboscidea, Elephantidae) during the Late Pleistocene in the Valsequillo Basin, Puebla, Mexico

Historical Biology, Год журнала: 2021, Номер 34(4), С. 750 - 758

Опубликована: Авг. 6, 2021

Mathematical models are a helpful tool that can help palaeoecology research advance in similar ways as the ones already used theoretical ecology. In this article, we use mathematical model based on differential equations to estimate past Mammuthus columbi population Valsequillo Basin, Puebla, Mexico. We calibrated biological and etiologic parameters of African elephant Loxodonta africana. addition mean population, analysis allows inferring dynamics M. Basin. The is ecological interactions between its food resource. It was found must have been oscillating before an equilibrium reached. Several potential scenarios on-site production (grass) here analysed. good efficiency find lead recurrent cycles abundance famine. situation, populations emigrate then immigrate periodic circles avoid starvation.

Язык: Английский

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