Insights into the early evolution of modern avian physiology from fossilized soft tissues from the Mesozoic

Philosophical Transactions of the Royal Society B Biological Sciences, Год журнала: 2025, Номер 380(1920)

Опубликована: Фев. 27, 2025

Modern birds (Neornithes) are the mostly highly modified group of amniotes, bearing little resemblance to other extant sauropsids. Archaeopteryx , with its nearly modern wings but plesiomorphic skeleton, demonstrated more than 160 years ago that soft tissue specializations preceded skeletal modifications for flight. Soft tissues thus great importance understanding early evolution avian physiology. Most commonly, traces integumentary system preserved; exceptional discoveries include remnants organs. Together, these have helped elucidate lungs, ovaries, plumage and beak in diverging birds. These fossils reveal many important adaptations efficient digestion, high oxygen intake, reduced body mass improved wing structure, all which serve improve aerial capabilities and/or meet energetic demands this costly form locomotion, evolved within first 20–30 Myr evolution. preservation also provides clues ecology may even extinction certain groups. However, current fossil record Mesozoic is almost entirely limited Early Cretaceous thus, from Late potential drastically transform our interpretation available data. This article part theme issue ‘The biology respiratory system’.

Язык: Английский

---

A New Era of Morphological Investigations: Reviewing Methods for Comparative Anatomical Studies

Integrative Organismal Biology, Год журнала: 2023, Номер 5(1)

Опубликована: Янв. 1, 2023

Synopsis The increased use of imaging technology in biological research has drastically altered morphological studies recent decades and allowed for the preservation important collection specimens alongside detailed visualization bony soft-tissue structures. Despite benefits associated with these newer techniques, there remains a need more “traditional” methods examination many comparative studies. In this paper, we describe costs various visualizing, examining, comparing There are significant differences not only different (monetary, time, equipment, software), but also degree to which destroyed. We argue any one particular method over another studies, instead suggest combination is useful breadth visualization, financial time constraints often imposed on early-career scientists.

Язык: Английский

---

Diet of Mesozoic toothed birds (Longipterygidae) inferred from quantitative analysis of extant avian diet proxies

BMC Biology, Год журнала: 2022, Номер 20(1)

Опубликована: Май 12, 2022

Birds are key indicator species in extant ecosystems, and thus we would expect extinct birds to provide insights into the nature of ancient ecosystems. However, many aspects bird ecology, particularly their diet, remain obscure. One group particular interest is bizarre toothed long-snouted longipterygid birds. Longipterygidae most well-understood family enantiornithine birds, dominant Cretaceous period. as with Mesozoic diet remains entirely speculative.

Язык: Английский

---

Exceptional preservation and foot structure reveal ecological transitions and lifestyles of early theropod flyers

Nature Communications, Год журнала: 2022, Номер 13(1)

Опубликована: Дек. 20, 2022

Abstract Morphology of keratinised toe pads and foot scales, hinging joints claw shape size all inform the grasping ability, cursoriality feeding mode living birds. Presented here is morphological evidence from fossil feet early theropod flyers. Foot soft tissues joint articulations are qualitatively assessed using laser-stimulated fluorescence. Pedal quantitatively analysed traditional morphometrics. We interpret these data among existing to better understand evolutionary ecology Jurassic flyers like Anchiornis Archaeopteryx show adaptations suggestive relatively ground-dwelling lifestyles. Early Cretaceous then diversify into more aerial lifestyles, including generalists Confuciusornis specialists climbing Fortunguavis . Some birds, Late Berlin Sapeornis , complex ecologies seemingly unique sampled modern As a non-bird flyer, finding affinities Microraptor specialised raptorial lifestyle unexpected. Its hawk-like characteristics rare known time suggesting that some perform roles filled by birds today. demonstrate diverse ecological profiles flyers, changing as flight developed, have roles.

Язык: Английский

---

Quantifying shape and ecology in avian pedal claws: The relationship between the bony core and keratinous sheath

Ecology and Evolution, Год журнала: 2019, Номер 9(20), С. 11545 - 11556

Опубликована: Сен. 30, 2019

Terrestrial tetrapods use their claws to interact with environments in a plethora of ways. Birds particular have developed diversity claw shapes since they are often not bound terrestrial locomotion and heterogeneous body masses ranging several orders magnitude. Numerous previous studies hypothesized connection between pedal shape ecological mode birds, yet generated conflicting results, spanning from clear groupings based on complete overlap modes. The majority these relied traditional morphometric arc measurements keratinous sheaths variably accounted for likely confounding factors such as mass phylogenetic relatedness. To better address the relationship ecology we collected 580 radiographs allowing visualization bony core sheath 21 avian orders. Geometric morphometrics was used quantify compared results using measurements. Neither approach significantly separates bird into coarse categories after integrating size relatedness; however, some separation groups is evident find gradual shift ground-dwelling birds those predatory birds. Further, correlated, degree functional integration does differ across groups. Therefore, it possible compare fossil cores extant applying corrections. Finally, metrics geometric significantly, loosely correlated. Based future workers encouraged approaches study geometry account size, phylogeny, individual variation prior predicting taxa.

Язык: Английский

---

The diet of early birds based on modern and fossil evidence and a new framework for its reconstruction

Biological reviews/Biological reviews of the Cambridge Philosophical Society, Год журнала: 2021, Номер 96(5), С. 2058 - 2112

Опубликована: Июль 8, 2021

Birds are some of the most diverse organisms on Earth, with species inhabiting a wide variety niches across every major biome. As such, birds vital to our understanding modern ecosystems. Unfortunately, evolutionary history ecosystems is hampered by knowledge gaps in origin bird diversity and ecosystem ecology. A crucial part addressing these shortcomings improving earliest birds, non-avian avialans (i.e. non-crown birds), particularly their diet. The diet has been matter debate, large because ambiguous qualitative approaches that have used reconstruct it. Here we review methods for determining fossil avians crown birds) as well theropods, comment usefulness when applied avialans. We use this propose set comparable, quantitative ascertain basis provide consensus what currently know about While no single approach can precisely predict each exclude diets narrow dietary possibilities. recommend combining (i) dental microwear, (ii) landmark-based muscular reconstruction, (iii) stable isotope geochemistry, (iv) body mass estimations, (v) traditional and/or geometric morphometric analysis, (vi) lever modelling, (vii) finite element analysis accurately. Our provides specific methodologies implement discusses complications future researchers should keep mind. note current forms assessment mesowear, skull morphometrics, certain systems yet be proven effective at discerning On report state avialan which remains very incomplete. ancestral condition unclear due scarce data contradictory evidence Archaeopteryx. Among early pygostylians, Confuciusornis mechanical advantage pointing herbivory, whilst Sapeornis only indicating granivory, agreeing fossilised ingested material known taxon. enantiornithine ornithothoracine Shenqiornis pedal carnivory. In hongshanornithid ornithuromorph Hongshanornis indicates but agrees gastrolith ingestion Mechanical fish support carnivory songlingornithid Yanornis. Due sparsity robust assignments, clear trends evolution emerged. Dietary seems increase through time, preservational bias associated predominance from Early Cretaceous Jehol Lagerstätte. With new framework synthesis diet, expect become much clearer coming years, especially fossils other locations climates found. This will allow deeper more role played Mesozoic how developed into pivotal

Язык: Английский

---

Functional morphology of vertebrate claws investigated using functionally based categories and multiple morphological metrics

Journal of Morphology, Год журнала: 2021, Номер 282(3), С. 449 - 471

Опубликована: Янв. 4, 2021

Abstract The link between claw morphology and function has been historically difficult to quantify, analyze, interpret. In this study, the functional of vertebrate claws is analyzed using measurements taken from 80 modern specimens spanning birds, mammals, one reptile. Claw were chosen for their potential biomechanical significance a revised, expanded categorization defined used. This scheme result an extensive literature review based on observed mechanics rather than animal's overall ecology, important departure norm followed in previous studies. A principal component analysis reveals that some morphological disparity related differences; however, different categories are not clearly separated solely morphology. linear discriminant successfully classifies 81.25% documented categories. When posterior probabilities each classification examined, next highest considered, able classify 96.25% specimens. Expressing angle terms lengths prior incorporating cross‐sectional shape data both serve reduce misclassification rate. use biomechanically meaningful (rather ecology) improves confidence ability infer methods. While most certainly multiple factors (e.g., growth, size, etc.), study establishes it reflects mechanical more previously demonstrated.

Язык: Английский

---

A new Archaeopteryx from the lower Tithonian Mörnsheim Formation at Mühlheim (Late Jurassic)

Fossil record, Год журнала: 2025, Номер 28(1), С. 17 - 43

Опубликована: Янв. 3, 2025

Here we describe a new specimen of Archaeopteryx sp. from the lower Tithonian Mörnsheim Formation in Franconian Alb Bavaria, Germany. This fossil is third avialan found this formation. The skeleton comprises right forelimb and shoulder as well fragments left both hind limbs. lengths humerus ulna are most similar to those Munich . Despite having been massively altered by late diagenesis, it can be referred sp., based on morphology furcula, coracoid, radius, manual ungual, which nests within morphospace rather than that Anchiornis Phylogenetic analyses also support assignment Due fossil’s state preservation, still-unresolved taxonomy genus species level, an identification beyond remains impossible.

Язык: Английский

---

A new Archaeopteryx from the lower Tithonian Mörnsheim Formation at Mühlheim (Late Jurassic)

Fossil record, Год журнала: 2025, Номер 28(1), С. 17 - 43

Опубликована: Янв. 3, 2025

Here we describe a new specimen of Archaeopteryx sp. from the lower Tithonian Mörnsheim Formation in Franconian Alb Bavaria, Germany. This fossil is third avialan found this formation. The skeleton comprises right forelimb and shoulder as well fragments left both hind limbs. lengths humerus ulna are most similar to those Munich . Despite having been massively altered by late diagenesis, it can be referred sp., based on morphology furcula, coracoid, radius, manual ungual, which nests within morphospace rather than that Anchiornis Phylogenetic analyses also support assignment Due fossil’s state preservation, still-unresolved taxonomy genus species level, an identification beyond remains impossible.

Язык: Английский

---

Osteology and functional morphology of a transitional pterosaur Dearc sgiathanach from the Middle Jurassic (Bathonian) of Scotland

BMC Ecology and Evolution, Год журнала: 2025, Номер 25(1)

Опубликована: Янв. 24, 2025

Abstract Pterosaurs were the first vertebrates to evolve active flight. The lack of many well-preserved pterosaur fossils limits our understanding functional anatomy and behavior these flight pioneers, particularly from their early history (Triassic Middle Jurassic). Here we describe in detail osteology an exceptionally preserved Jurassic pterosaur, holotype Dearc sgiathanach Isle Skye, Scotland. We identify new autapomorphies apparatus (humerus sternum), which further support distinctiveness compared with other early-diverging pterosaurs features, such as vertebral morphology, shared later-diverging that probably developed convergently a large body size or sign modular evolution. used extant phylogenetic bracketing infer principal cranial antebrachial musculature, indicating had anteriorly placed palatal musculature compensated for weak temporal jaw adductors wing suggestive style reliant on powerful adduction protraction humerus. Comparisons revealed non-pterodactyloids , despite overall conservative bauplans, adapted various feeding styles. myology are indicative predator flew hunted above lagoons nearshore environments Jurassic.

Язык: Английский

---