Variation of population and community ecology over large spatial scales in Ediacaran early animal communities
Notice bibliographique
Résumé
The Ediacaran strata of Newfoundland, Canada (580–560 Ma) record some of the first animal communities. The in-situ preservation of these sessile organisms means that the positions and sizes of specimens on the bedding planes encapsulate their life-histories, enabling spatial analyses to reconstruct their ecological dynamics. However, it is not known how these Ediacaran ecological dynamics vary across large spatial scales. Fortunately, the E and G surfaces at Mistaken Point, Newfoundland (∼565 Ma) crop out at multiple locations, providing the opportunity to compare ecological dynamics between communities separated by large spatial scales (∼800 m). In this study, we collected data from two outcrops each of E and G surfaces using a combination of laser-line probe, LiDAR and photogrammetry. We mapped out Mistaken Point G surface over 7.22 m 2 , finding 9 frondose taxa across 158 specimens Watern Cove East G surface across 154 m 2 (93 m 2 when fractures are excluded) finding 19 frondose taxa across 1320 specimens; and Watern Cove West E Surface across 20.02 m 2 , finding 11 frondose taxa across 734 specimens. We compared the Watern Cove West E surface with previously collected data from Mistaken Point E Surface, which had 2977 specimens over 85.42 m 2 . The two G outcrops exhibited remarkably similar community compositions, both dominated by Bradgatia with high proportions of frondose rangeomorphs and arboreomorphs. In contrast, the compositions between the E surfaces were notably different, with Watern Cove West E surface showing relatively higher proportions of Fractofusus and Bradgatia and lower proportions of frondose taxa . For comparisons of population ecology between the outcrops, only Bradgatia (G) and Fractofusus (E) populations occurred in sufficient numbers to enable spatial analyses. We quantified the spatial distributions using spatial point process analyses, finding for E surfaces that the Fractofusus populations showed significantly similar spatial patterns, which indicated reproductive events. In contrast, on G surface, the Bradgatia populations show remarkably different underlying processes, with the Watern Cove East population showing reproductive clusters on a background environmental heterogeneity, whereas the Mistaken Point population shows spatial segregation, indicating intra-specific competition. The Watern Cove East Bradgatia have a much lower density than those on Mistaken Point, suggesting that the increased density leads to competition due to insufficient resources to maintain this higher density. In modern deep-sea benthic communities, increased population densities occur within communities when different areas are subject to different flow regimes, and so different nutrient flux. Our results suggest that the Ediacaran communities of Mistaken Point show variability in ecological dynamics, even while composition of these communities remain remarkably similar. • Multiple Ediacaran surfaces enable analysis of large-scale community ecology. • Biological differences in community composition are distinguishable from PFPs. • Density and community dynamics can differ even if community composition is consistent. • The only taxon with small-scale intra-specific competition has a large wake. • Ediacaran community but not regional ecology are comparable to modern.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».