eJournal
1. Tiktaalik
https://www.palaeocast.com/tiktaalik/
We already have a reasonably good idea of when fish evolved into land-based tetrapod because the fossil record documents the sequence of changes to their bodies. One of the most iconic specimens is Tiktaalik, a "transitional" fossil dating to around 375 million years ago. Tiktaalik is special, because though it retains many fish-like characteristics, it also possesses wrist bones, suggesting that it could support itself on its front limbs. Fossils from rocks older than Tiktaalik lack these wrist bones and are generally more fish-like. Fossils from younger rocks include more tetrapod-like species, with distinct digits and limbs.
Walking fish help people understand how we left the ocean. Our ancestors' transition out of the water and onto the land was a pivotal moment in evolution. No longer buoyed by water, early tetrapods had to overcome gravity in order to move their bodies. Exactly how those early pioneers first evolved the fundamental capacity to walk has fascinated scientists for many years.
2. News
Study: Hands of “Ardi” Indicate a Chimp-like Tree-Dweller and Knuckle-Walker
Recently we saw that a new study found the supposed human ancestor Sahelanthropus Tchadensis had a chimp-like quadruped body plan. It therefore should not be considered a human ancestor. The hominin fossil Ardipithecus ramidus, or “Ardi,” has been going through a similar evolution. Initially, Ardi was widely called the “oldest human ancestor,” due to its supposed skeletal traits that indicated an early bipedal (upright walking) species. Lead researcher Tim White even called Ardi the “Rosetta stone for understanding bipedalism.” But after Ardi was officially announced, other papers strongly challenged the claim that Ardi was bipedal. One article in Science commented that “All of the Ar. ramidus bipedal characters cited also serve the mechanical requisites of quadrupedality.” Another review in Nature strongly argued that “the claim that Ardipithecus ramidus was a facultative terrestrial biped is vitiated because it is based on highly speculative inferences about the presence of lumbar lordosis and on relatively few features of the pelvis and foot.”
It must be the most common picture that used to explain the concept ‘evolution’. The new discovery ‘Ardi’ attracts me that people may find another good example to help us understand how we evolved into bipedalism.
3. Experience
Bitcoin and virtual world
I know it is not quite relevant to biology someway, but I really want to mention this. Bitcoin is a type of cryptocurrency. There are no physical bitcoins, only balances kept on a public ledger that everyone has transparent access to. All bitcoin transactions are verified by a massive amount of computing power. Bitcoins are not issued or backed by any banks or governments, nor are individual bitcoins valuable as a commodity.
Every country issues its own currency that is regulated by the corresponding government. We all know the function of currency in global economy and how important it is. I think the development of bitcoin is also an evolution of real gold coin to virtual currency. From my perspective, when currency enters a virtual world, all living things will enter the virtual world as well.
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