Mats Eriksson
Professor
Molecular and microstructural inventory of an isolated fossil bird feather from the Eocene Fur Formation of Denmark
Författare
Summary, in Swedish
An isolated, yet virtually intact contour feather
(FUM-1980) from the lower Eocene Fur Formation of Denmark
was analysed using multiple imaging and molecular
techniques, including field emission gun scanning electron
microscopy (FEG-SEM), X-ray absorption spectroscopy and
time-of-flight secondary ion mass spectrometry (ToF-SIMS).
Additionally, synchrotron radiation X-ray tomographic
microscopy (SRXTM) was employed in order to produce a
digital reconstruction of the fossil. Under FEG-SEM, the
proximal, plumulaceous part of the feather revealed masses
of ovoid microstructures, about 1.7 µm long and 0.5 µm
wide. Microbodies in the distal, pennaceous portion were
substantially smaller (averaging 0.9 x 0.2 µm), highly elongate,
and more densely packed. Generally, the microbodies
in both the plumulaceous and pennaceous segments were
aligned along the barbs and located within shallow depressions
on the exposed surfaces. Biomarkers consistent with
animal eumelanins were co-localized with the microstructures,
to suggest that they represent remnant eumelanosomes
(i.e. eumelanin-housing cellular organelles). Additionally,
ToF-SIMS analysis revealed the presence of sulfur-containing
organics – potentially indicative of pheomelanins – associated
with eumelanin-like compounds. However, since there
was no correlation between melanosome morphology and
sulfur content, we conclude these molecular structures derive
from diagenetically incorporated sulfur rather than pheomelanin.
Melanosomes corresponding roughly in both size and
morphology with those in the proximal part of FUM-1980
are known from contour feathers of extant parrots (Psittaciformes),
an avian clade that has previously been reported
from the Fur Formation.
(FUM-1980) from the lower Eocene Fur Formation of Denmark
was analysed using multiple imaging and molecular
techniques, including field emission gun scanning electron
microscopy (FEG-SEM), X-ray absorption spectroscopy and
time-of-flight secondary ion mass spectrometry (ToF-SIMS).
Additionally, synchrotron radiation X-ray tomographic
microscopy (SRXTM) was employed in order to produce a
digital reconstruction of the fossil. Under FEG-SEM, the
proximal, plumulaceous part of the feather revealed masses
of ovoid microstructures, about 1.7 µm long and 0.5 µm
wide. Microbodies in the distal, pennaceous portion were
substantially smaller (averaging 0.9 x 0.2 µm), highly elongate,
and more densely packed. Generally, the microbodies
in both the plumulaceous and pennaceous segments were
aligned along the barbs and located within shallow depressions
on the exposed surfaces. Biomarkers consistent with
animal eumelanins were co-localized with the microstructures,
to suggest that they represent remnant eumelanosomes
(i.e. eumelanin-housing cellular organelles). Additionally,
ToF-SIMS analysis revealed the presence of sulfur-containing
organics – potentially indicative of pheomelanins – associated
with eumelanin-like compounds. However, since there
was no correlation between melanosome morphology and
sulfur content, we conclude these molecular structures derive
from diagenetically incorporated sulfur rather than pheomelanin.
Melanosomes corresponding roughly in both size and
morphology with those in the proximal part of FUM-1980
are known from contour feathers of extant parrots (Psittaciformes),
an avian clade that has previously been reported
from the Fur Formation.
Avdelning/ar
- Berggrundsgeologi
- MAX IV-laboratoriet
- Functional zoology
- Syngruppen
- Kemisk fysik
Publiceringsår
2017-01-01
Språk
Engelska
Sidor
73-90
Publikation/Tidskrift/Serie
Palaeontology
Volym
60
Issue
1
Dokumenttyp
Artikel i tidskrift
Förlag
Wiley-Blackwell
Ämne
- Other Earth and Related Environmental Sciences
- Geology
Aktiv
Published
Forskningsgrupp
- Lund Vision Group
ISBN/ISSN/Övrigt
- ISSN: 1475-4983