Morocco 2015
"Rocks and Fossils of Morocco"
Issue Date |
09.10.2015 |
ID |
Michel: 1876-1879;
Scott: 1208-1211;
Stanley Gibbons:
Yvert et Tellier: 1713-1716;
Category: pF |
Design |
|
Stamps in set |
4 |
Value |
3.75 - Stromatolite
3.75 - Marrellomorph
9.00 - Aegirocassis
9.00 - Tissint_meteorite
|
Size (width x height) |
40 mm x 30 mm;
30 mm x 40 mm
|
Layout |
Sheets of 25 stamps |
Products |
FDC x 1 |
Paper |
|
Perforation |
13 x 13 |
Print Technique |
Offset |
Printed by |
Philaposte France |
Quantity |
|
Issuing Authority |
Barid Al-Maghrib |
On October 9
th, 2015,
on the occasion of the international conference "RALI 2015- The Rise of Animal Life",
which took place in Marrakesh between October 5 and October 10 2015, organized
under the High Patronage of His Majesty King Mohamed VI, the Cadi Ayyad
University, under the themes of the Cambrian Explosion and Great
biodiversification Cambrian and the Promotion of the Geological
Heritage, Barid Al-Maghrib, the Post Authority of Morocco issued the set of 4 stamps
"Rocks and Fossils of Morocco".
The formal theme of the meeting is devoted to "Cambrian and Ordovician radiations".
In conjunction with the conference, a special symposium dedicated to aspects of
Geological Heritage was held and highlighted associated educational, cultural and socio-economic issues.
The scientific sessions were followed by a field trip, a “Geotraverse of Central High Atlas and Anti- Atlas.
This field trip offered participants the opportunity to visit fossil localities near Zagora, where
the
Fezouata Biota is currently being studied by an international team of scientists.
In the Ternata plain (N. of Zagora), the Lower Ordovician succession (Fezouata Shale and Zini Sandstones)
lies unconformably over the middle Cambrian Tabanite Group.
The Fezouata Shale corresponds to a thick monotonous series (1000 m) of siltstones deposited under shallow
offshore conditions (storm-wave influence).
The Fezouata Biota provides a unique insight into one of the most critical periods in the evolution
of marine life: the Cambrian-Ordovician transition.
The following fossils and mineral were depicted on the stamps
Stromatolites or stromatoliths are layered bio-chemical accretionary structures
formed in shallow water by the trapping, binding and cementation of sedimentary grains
by biofilms (microbial mats) of microorganisms, especially cyanobacteria.
|
Stromatolite on stamp of Morocco 2015
MiNr.: 1876, Scott: 1208.
|
Fossilized stromatolites provide ancient records of life on Earth by these remains, which might date from more
than 3.5 billion years.
A variety of stromatolite morphologies exists, including conical, stratiform, branching, domal, and columnar types.
Stromatolites occur widely in the fossil record of the Precambrian, but are rare today.
Very few ancient stromatolites contain fossilized microbes.
While features of some stromatolites are suggestive of biological activity, others possess features
that are more consistent with abiotic (non-biological) precipitation.
Finding reliable ways to distinguish between biologically formed and abiotic stromatolites
is an active area of research in geology.
There are only two more stamps and one commemorative postmark depicting stromatolites
issued to date:
The second stamp shows a
Marrellomorph arthropod from Zagora region of Morocco, discovered by
Mohamed Benmoulai, local collector and it is the first time when fossilized soft tissue of the species is found
which is very rare for arthropods.
|
Marrellomorph on stamp of Morocco 2015
MiNr.: 1877, Scott: 1209.
|
Marrella itself is a small animal, 2 cm or less in length.
The head shield has two pairs of long rearward spikes.
On the underside of the head are two pairs of antennae, one long and sweeping, the second shorter and stouter.
Marrella has a body composed of 24–26 body segments, each with a pair of branched appendages.
The lower branch of each appendage is a leg for walking, while the upper branch is a long, feathery gill.
There is a tiny, button-like telson at the end of the thorax.
It is unclear how the unmineralized head and spines were stiffened.
Marrella has too many antennae, too few cephalic legs, and too few segments per leg to
be a trilobite.
It lacks the three pairs of legs behind the mouth that are characteristic of crustacea.
The legs are also quite different from those of crustaceans.
The identification of a diffraction grating pattern on well-preserved
Marrella specimens proves
that it would have harboured an iridescent sheen—and thus would have appeared colourful.
Dark stains are often present at the posterior regions of specimens,
probably representing extruded waste matter.
On March 12, 2015, SciTech Daily website reports about newly discovered fossils of an extinct
sea creature named
Aegirocassis benmoulae
which provides key evidence about the early evolution of arthropods.
|
Aegirocassis on stamp of Morocco 2015
MiNr.: 1878, Scott: 1210.
|
The new animal, named
Aegirocassis benmoulae in honor of its discoverer, Mohamed Ben Moula,
attained a size of at least 2 meters, ranking it among the biggest arthropods that ever lived.
It was found in south-eastern Morocco and dates back some 480 million years.
“
Aegirocassis is a truly remarkable looking creature,” said Yale University paleontologist Derek Briggs,
co-author of a Nature paper describing the animal.
We were excited to discover that it shows
features that have not been observed in older Cambrian anomalocaridids
— not one but two sets of swimming flaps along the trunk, representing
a stage in the evolution of the two-branched limb, characteristic of
modern arthropods such as shrimps.
The recent discovery of
Aegirocassis benmoulae bring new details
at arthropods story.
The new animal shows that anomalocaridids in fact had two separate sets of flaps per segment.
The upper flaps were equivalent to the upper limb branch of modern arthropods, while
the lower flaps represent modified walking limbs, adapted for swimming.
Furthermore, a re-examination of older anomalocaridids showed that these flaps also were
present in other species, but had been overlooked.
These findings show that anomalocaridids represent a stage before the fusion of the upper and
lower branches into the double-branched limb of modern arthopods.
Aegirocassis benmoulae is also remarkable from an ecological
standpoint, note the researchers.
While almost all other anomalocaridids were active predators that grabbed their prey with
their spiny head limbs, the Moroccan fossil has head appendages that
are modified into an intricate filter-feeding apparatus.
This means that the animal could harvest plankton from the oceans.
“Giant filter-feeding sharks and whales arose at the time of a major plankton
radiation, and
Aegirocassis represents a much, much older example of
this — apparently overarching — trend,” said Dr. Van Roy is one of the
authors of a new study that has shed light on the early evolution and
development of arthropod limbs.
|
Tissint_meteorite on stamp of Morocco 2015
MiNr.: 1879, Scott: 1211.
|
The last stamp of the set shows the Tissint Meteorite that fell in Tata Province
in the Guelmim-Es Semara region of Morocco on July 18, 2011.
Tissint is only the fifth Martian meteorite (A Martian meteorite is a rock that formed
on the planet Mars and was then ejected from Mars by the impact of an asteroid or comet,
and finally landed on the Earth) that people have witnessed falling to Earth, the last time in 1962.
Pieces of the meteorite are on display at several museums, including the Museum of Natural History of Vienna
and the Natural History Museum in London.
The Tissint meteorite, a piece of Mars that crashed into Earth in July 2011, may contain proof of ancient
life on the red planet, according to a new study.
The researchers believe organic carbon found within the meteorite is Martian in origin and may have been created by
biologic processes.
Recent research estimates the Tissint meteorite was ejected from Mars about 700,000 years ago and may have been
formed 400 million to 500 million years ago.
Products and associated philatelic items
FDC |
Examples of circulated covers |
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The same cover, but different postmark. |
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References
Acknowledgements:
- Many thanks to Dr. Peter Voice from Department of Geological and Environmental Sciences,
Western Michigan University, for reviewing the draft page and his valuable comments.