Bangiomorpha pubescens
| Bangiomorpha pubescens | |
|---|---|
.jpg) | |
| Bevaringsstatus | |
| Kendes kun fra fossiler Geologisk tidsalder: | |
| Videnskabelig klassifikation | |
| Rige | Protista (Protister) |
| Række | Rhodophyta |
| Klasse | Bangiophyceae |
| Orden | Bangiales |
| Familie | Bangiaceae |
| Slægt | Bangiomorpha |
| Art | B. pubescens |
| Videnskabeligt artsnavn | |
| Bangiomorpha pubescens | |
| Hjælp til læsning af taksobokse | |
Bangiomorpha pubescens er en fossil rødalge, fundet i Canada (usikre fund som måske er denne art kendes fra Grønland). Den er det tidligste eksempel på kompleks flercellet liv, idet den har et fasthæftningsorgan og dermed har den kunnet stå lodret i strandkanten. Den er dateret til at være 1200 millioner år gammel (+/- 24 mill. år). Denne er den første kønnede organisme – og kønnethed anses derfor at være forudsætning for kompleks flercellethed og organeldannelse.
Den ligner forbløffende meget en nulevende rødalge, Bangia.
Referencer
- ↑ Butterfield, Nicholas J. (2000). "Bangiomorpha pubescens n. gen., n. sp.: implications for the evolution of sex, multicellularity, and the Mesoproterozoic/Neoproterozoic radiation of eukaryotes". Paleobiology. 26 (3): 386-404. doi:10.1666/0094-8373(2000)026<0386:BPNGNS>2.0.CO;2. Citat: "...Multicellular filaments from the ca. 1200-Ma Hunting Formation (Somerset Island, arctic Canada) are identified as bangiacean red algae on the basis of diagnostic cell-division patterns. As the oldest taxonomically resolved eukaryote on record Bangiomorpha pubescens n. gen. n. sp. provides a key datum point for constraining protistan phylogeny...Differential spore/gamete formation shows Bangiomorpha pubescens to have been sexually reproducing, the oldest reported occurrence in the fossil record..."
- ↑ Gibson, Timothy M; Shih, Patrick M; Cumming, Vivien M; Fischer, Woodward W; Crockford, Peter W; Hodgskiss, Malcolm S.W; Wörndle, Sarah; Creaser, Robert A; Rainbird, Robert H; Skulski, Thomas M; Halverson, Galen P (2017). "Precise age of Bangiomorpha pubescens dates the origin of eukaryotic photosynthesis" (PDF). Geology. 46 (2): 135-138. doi:10.1130/G39829.1.
- ↑ December 20, 2017, By McGill University: Researchers Date the Origins of Photosynthesis to 1.25 Billion Years Ago, backup Citat: "...The world’s oldest algae fossils are a billion years old, according to a new analysis by earth scientists at McGill University. Based on this finding, the researchers also estimate that the basis for photosynthesis in today’s plants was set in place 1.25 billion years ago. The study, published in the journal Geology, could resolve a long-standing mystery over the age of the fossilized algae, Bangiomorpha pubescens, which were first discovered in rocks in Arctic Canada in 1990...Once the researchers had gauged the fossils’ age at 1.047 billion years, they plugged that figure into a “molecular clock,” a computer model used to calculate evolutionary events based on rates of genetic mutations. Their conclusion: the chloroplast must have been incorporated into eukaryotes roughly 1.25 billion years ago..."
- Bangiomorpha er omfattende beskrevet på dansk i en artikel i BioNyt – Videnskabens Verden nr.134/135 (2006) om livets opståen og udvikling.