Regressive evolution, often referred to as ‘evolution in reverse,’ raises questions about the possibility of biological structures returning to earlier, less intricate states. Take, for instance, the intriguing case of myxozoans, who come from the same family as jellyfish. These seemingly simple parasites lack complex anatomical structures like mouths, nervous systems, or guts. Through the course of evolution, they shed features they no longer needed due to their parasitic lifestyle.

While the term ‘regressive evolution’ might evoke images of organisms reverting to primitive forms, the reality is more nuanced. Let’s take the example of eye loss in cave-dwelling creatures like cavefish. As these organisms adapt to their light-deprived environments, they undergo changes that lead to the loss of their eyes. However, this doesn’t mean a complete reversal to become like an ancestor lacking eyes. Instead, the evolutionary process halts partway, resulting in vestigial eyes covered with skin. This exemplifies how evolution involves adjustments to suit the new environment.

A deeper exploration into regressive evolution reveals the underlying complexity of adaptation. It’s not as simple as just rolling back specific changes. Evolution is a network of interconnected modifications, with adaptations leading to further changes. For instance, when an organism develops a complex feature, such as an eye, it involves alterations – not only to the genes responsible for vision but also to the overall skull structure. Attempting to revert a single change would require a cascade of alterations, making true reversal exceedingly delicate.

Adding a new feather to his cap, Tesla CEO Elon Musk has now been inducted into the board of directors of Twitter. He’s going to be a class II director on the board until 2024. The classified board system of Twitter places the board members in corresponding terms to prevent a freshly-appointed member from gaining full control over the whole company. The news was announced in a filing with the US Securities and Exchange Commission (SEC) and has been confirmed by the tweets of both Musk and Twitter CEO Parag Agarwal.

The Tweets

In a series of tweets, Parag Agarwal confirmed the new role of Musk on the Twitter board. Calling Musk both a believer and critic of the service, Agarwal said that he was exactly what was needed to be included in the boardroom, and stated his assurance that Musk would bring great value to the board. In response to his welcoming tweet, Elon Musk tweeted back by saying that he looks forward to making great improvements to Twitter in near future.

The Filing

Recently, Elon Musk announced via a filing with the SEC about his purchase of a 9.2% stake in Twitter. Despite his repeated complaints about the absence of freedom of speech on the platform, this acquisition has made him the largest individual shareholder in the social media company. Musk’s appointment as a board member in Twitter was announced in another SEC filing, which determined the term of this new position until the 2024 Annual Meeting of Stockholders of Twitter. Limiting certain boundaries, the filing also clearly stated that during his service as a board member and for 90 days thereafter, Elon Musk can’t be the owner of more than 14.9% of Twitter’s common stock, either alone or as a member of a group. Former Twitter CEO Jack Dorsey has also warmly welcomed Musk to the board. Musk, however, is working on buying out the entirety of Twitter.