Twitter Article Assignment

Source Tweet: @NatGeo “This entire week, we are celebrating what scientists have unearthed
about the secrets of dinosaurs in recent years: on.natgeo.com/2GuvgX7
#NatGeoReimaginingDinos”. Twitter, 5 Oct. 2020, 6:31 am.,
https://twitter.com/NatGeo/status/1313109553916137472
Interesting Dinosaur Discoveries of 2020
By: Ciara Walton
With the beginning of this new decade, 2020 has brought access to new scientific understandings
and tools, we have made big leaps in discoveries on dinosaurs. A recent tweet thread by National
Geographic was intriguing, so here is some research on new dinosaur science discoveries. There
is a new theory on theropods using tail-propulsion, a theory on dinosaur eggs, and a new
dinosaur species. These discoveries can help us understand evolutionary theories better and
attain an increased understanding of how dinosaurs lived.
The ​Nature​ journal article is on a new theory of how theropod dinosaurs might have used
tail-propulsion in aquatic environments. This is a fairly new theory based on the tall neural
spines and elongated chevrons (a fin-like organ) which would allow it greater swimming ability
than that of other terrestrial dinosaurs. This theory, and those like it, were previously abandoned,
but this species of spinosaurids is discovered to have been at least partly aquatic due to its diet
and biomechanical bone structure.
Another ​Nature​ journal article is on the new theory that the first dinosaur eggs were soft, like
most mammalian species. It was previously believed that the first eggs were calcified or hard for
protection against environmental stressors and embryo viability. This study uses statistical

analysis of the “mineralogical, organochemical, and ultrastructural evidence ​for an originally
non-biomineralized, soft-shelled nature of exceptionally preserved ornithischian ​Protoceratops
and basal sauropodomorph ​Mussaurus​ eggs” to prove that the first dinosaur eggs were soft. After
comparing the “ancestral-state reconstruction of composition and ultrastructure” of
Protoceratops​ and ​Mussaurus​ with other diapsids, they prove that the first dinosaur egg was
soft-shelled and that the calcified, hard-shelled egg evolved later, throughout the Mesozoic era.
A further discovery from the ​Journal of Vertebrate Paleontology​ is on the discovery of a new
dinosaur in the nothosauroid family. They base this discovery on the finding of two unique
almost complete skeletons in China. The skeletal structure indicates it may have been a slow
underwater swimmer with a benthic (bottom feeder) carnivorous diet. According to this article,
this discovery contributes to the “​local faunal diversity and expands the known range of
sauropterygian lifestyles during the late Middle Triassic” as well as an opportunity to “test the
phylogenetic relationships of the Eosauropterygia hypothesized by previous studies”. In other
words, this discovery increases the known local lifeforms and range of sauropterygian creatures
in the late Middle Triassic period, while also providing an opportunity to test what is known or
hypothesized about the evolutionary history and relationships of all Sauropterygia.
With these new amazing discoveries and theories, paleontologists and evolutionary scientists can
use this new information to further their studies and theories. Some of the new discoveries
include a case of terminal cancer in a dinosaur and another new species of dinosaur on the Isle of
Wight. These discoveries could also help scientists understand and find cures for diseases and
cancers by understanding how they evolved with time.

Citations :
Qing-Hua Shang ​et al​. “A New Ladinian Nothosauroid (Sauropterygia) from Fuyuan, Yunnan
Province, China”. ​Journal of Vertebrate Paleontology​, published online October 29, 2020; doi:
10.1080/02724634.2020.1789651
Norell, M.A., Wiemann, J., Fabbri, M. ​et al.​ “The first dinosaur egg was soft”. ​Nature​ 583,
406–410 (2020). https://doi-org.proxy.lib.pdx.edu/10.1038/s41586-020-2412-8
Ibrahim, N., Maganuco, S., Dal Sasso, C. ​et al.​ “Tail-propelled aquatic locomotion in a theropod
dinosaur”. ​Nature​ 581, 67–70 (2020).
https://doi-org.proxy.lib.pdx.edu/10.1038/s41586-020-2190-3
Part Two: