Fosil Mirip kadal tertua ditemukan , petunjuk asal bersisik--T-REC-komunitas reptil-semarang--KSE-komunitas satwa eksotik

SILAHKAN MENGGUNAKAN " MESIN TRANSLATE "..GOOGLE TRANSLATE
DISAMPING KANAN INI.............

PLEASE USE ........ "TRANSLATE MACHINE" .. GOOGLE TRANSLATE BESIDE RIGHT THIS

.................


T-REC -TUGUMUDA REPTILES COMMUNITY-INDONESIA


More info :
www.trecsemarang2011.blogspot.com
minat gabung : ( menerima keanggotaan seluruh kota dan daerah di Indonesia )
08995557626
..................................
KSE – KOMUNITAS SATWA EKSOTIK – EXOTIC PETS COMMUNITY-- INDONESIA
Visit Our Community and Joint W/ Us....Welcome All Over The World
www.facebook.com/groups/komunitassatwaeksotik/
 KSE = KOMUNITAS SATWA EKSOTIK

MENGATASI KENDALA MINAT DAN JARAK

KAMI ADA DI TIAP KOTA DI INDONESIA
DETAIL TENTANG KSE-----KLIK : www.komunitassatwaeksotik-pendaftaran.blogspot.com

GABUNG......... ( menerima keanggotaan seluruh kota dan daerah di Indonesia )
HUBUNGI   :  089617123865

.........................

Fosil Mirip kadal tertua ditemukan , petunjuk asal bersisik

Sisa-sisa fosil reptil terkait erat dengan kadal yang tertua ditemukan . Dua rahang fosil yang ditemukan di Vellberg , Jerman memberikan bukti langsung pertama bahwa nenek moyang kadal , ular dan tuatara ( dikenal secara kolektif sebagai lepidosaurs ) masih hidup selama Trias Tengah periode - sekitar 240 juta tahun yang lalu ....more

Oldest lizard-like fossil yet to be
found hints at scaly origins

Date:

September 24, 2013

Source:

University College London

Summary:

The fossilized remains of a reptile closely related to lizards are the
oldest yet to be discovered. Two new fossil jaws discovered in Vellberg,
Germany provide the first direct evidence that the ancestors of lizards, snakes
and tuatara (known collectively as lepidosaurs) were alive during the Middle
Triassic period -- around 240 million years ago.

.................

The fossilised remains of a reptile closely related to lizards are the
oldest yet to be discovered.

Two new fossil jaws discovered in Vellberg, Germany provide the first
direct evidence that the ancestors of lizards, snakes and tuatara (known
collectively as lepidosaurs) were alive during the Middle Triassic period --
around 240 million years ago.

The new fossil finds predate all other lepidosaur records by 12 million
years. The findings are published in BMC Evolutionary Biology.

The international team of scientists who dated the fossil jaws have
provided evidence that lepidosaurs first appeared after the end-Permian mass
extinction event, a period when fauna began to recover and thrive in the more
humid climate.

Lead author Dr Marc Jones, who conducted the research at UCL, explained:
"The Middle Triassic represents a time when the world has recovered from
the Permian mass extinction but is not yet dominated by dinosaurs. This is also
when familiar groups, such as frogs and lizards, may have first appeared."

The small teeth and lightly built jaws suggest that the extinct animal
preyed on small insects. The new fossils are most closely related to the
tuatara, a lizard-like reptile.

Tuatara can be found on 35 islands lying off the coast of New Zealand and
were recently reintroduced to the mainland. However, they are the sole
survivors of a group that was once as globally widespread as lizards are today.
Tuatara feed on beetles, spiders, crickets and small lizards, also enjoying the
occasional sea bird.

Today, there are over 9,000 species of lizards, snakes and tuatara. Knowing
when the common ancestor of this grouping first appeared is crucial for
understanding the ecological context in which it first evolved as well as its
subsequent diversification.

To establish the age of the fossil remains, biologists use a dating
technique known as a "molecular clock." This method compares the
amount of genetic divergence between living animals, caused by changes in their
DNA sequences that have accumulated since they split from a common ancestor.
These mutations occur fairly regularly, ticking along at a clock-like rate.
However, for the clock to convert genetic differences into geological time, it
has to be calibrated using one or more fossils of known relationship and time.

Molecular clocks have been used by biologists to answer questions as
important as when the first modern humans emerged, and when humans and
chimpanzees shared a common ancestor. The new fossil jaws can improve molecular
dating estimates of when reptiles began to diversify into snakes, lizard and
tuatara, and when the first modern lizards inhabited the earth. Previous
estimates have varied over a range of 64 million years and the team are keen to
help narrow this down.

"Some previous estimates based on molecular data suggested that
lizards first evolved 290 million years ago," said second author Cajsa
Lisa Anderson, University of Gothenburg. "To a palaeontologist this seems
way too old and our revised molecular analysis agrees with the fossils."

Revised molecular dating in light of this new fossil find now suggests
lizards began to diversify into most of the modern groups we recognise today,
such as geckos and skinks, less than 150 million years ago in the Cretaceous
period, following continental fragmentation.

The specimens were collected and initially identified by Professor Rainer
Schoch from the Staatliches Museum für Naturkunde in Stuttgart, where the
specimens are now registered.

Scientists anticipate that the Vellberg site will yield yet more fossil discoveries
in the future, broadening our knowledge of the vertebrate fossil record.

Co-Author Professor Susan Evans, from the UCL Department of Cell and
Developmental Biology, said: "The fossil record of small animals such as
lizards and frogs is very patchy. Hopefully, this new fossil site in Germany
will eventually give us a broader understanding of what was going on at this
time."







Story Source:

The above story is based on materials provided
by University College London. Note:
Materials may be edited for content and length.







Journal Reference:

1.   
Marc EH Jones, Cajsa Lisa Anderson, Christy A Hipsley, Johannes Müller,
Susan E Evans, Rainer R Schoch.Integration of molecules and new fossils
supports a Triassic origin for Lepidosauria (lizards, snakes, and tuatara). BMC
Evolutionary Biology, 2013; 13 (1): 208 DOI:10.1186/1471-2148-13-208

http://www.sciencedaily.com/releases/2013/09/130924193616.htm

Share this: