On the whole, it might be easier to conclude that the timing is somewhat off than that complex life started without oxygen. But symbiosis is an intriguing theory nonetheless.
Cell biology
Researchers: Cells organize themselves in our organs by increasing in volume when tissues bend
“The fact that this increase in volume is staggered in time and transient also shows that it is an active and living system,” adds a researcher. Once again, we are expected to believe that such a system can just develop in a gradual Darwinian fashion.
Researchers: A key cell division protein is still a puzzle
In other words, contrary to expectation, the system is even more complex than supposed. At this point, unguided evolution becomes overwhelmingly implausible because it would take only one misstep to end the process. But people believe what they believe.
Before dividing, cells toss out waste products
Researcher: “Our hypothesis is that cells might be throwing out things that are building up, toxic components or just things that don’t function properly that you don’t want to have there. It could allow the newborn cells to be born with more functional contents,” says Teemu Miettinen, an MIT research scientist and the lead author of the new study.
David Coppedge on cell division as another “hurdle for evolution”
Coppedge: The two daughter cells face a massive organization problem. Even though they contain the same DNA code, they will take on separate roles in the cell. This means that the accessibility of genes between the two cells must radically differ.
Researchers: Animals age at the same rate despite big variations in lifespan and size
At ScienceDaily: Researchers from the Wellcome Sanger Institute found that despite huge variation in lifespan and size, different animal species end their natural life with similar numbers of genetic changes.
More depths to the bacterial flagellum: Mysterious protein FliL now better understood
Researcher: “We’ve made incremental progress in understanding this fascinating machine,” says Liu. “We hope to continue to work on this for decades to solve how the flagella of different bacteria uniquely evolved. We’ve just touched the tip of the iceberg of understanding this beautiful structure.”
What about the idea that cells were once much simpler? But how much simpler?
Introducing the third vid in the Long Story Short series (on cell membranes) Rob Stadler comments: First, scientists have been working for decades to simplify existing life, trying to arrive at a minimal viable life form by jettisoning anything that is not essential from the simplest extant cells. The success of Craig Venter’s group is Read More…
Film premieres today: Cell membranes as a challenge in the origin of life
This is the third of several episodes about the origin of life presented as part of the Long Story Short series — an education you actually have time for.
Confounding scientists for decades, RNA switches “on” and “off”
Unlike anything we know in the real world, all this complex machinery that confounds us just somehow, rather quickly, fell into place.
Our cells even have tentacles
So the little blobs aren’t nearly as helpless, let alone simple, as they have sometimes been made out to be. It’s quite the little world in there. Unfortunately, some of the cells that probably get a lot of use out of their filapodia are cancer cells. But maybe, the researchers suggest, that fact points to new treatment methods.
The more we study kinesin, the more remarkable it appears
David Coppedge: Cells are inhabited by molecular motors and engines with precision parts operating under tight regulations.
Origin of life: But how do cells come to have “borders” at all?
Inanimate objects don’t have “borders” because they need not defend themselves against anything. Boulders don’t care if they end up as sand. Having a membrane at all suggests that something is different about life that can’t be explained by the various “It all just happened” scenarios we often hear about how life got started. How did life forms decide they wanted to protect themselves?
Charming bacteria set off virus bombs in their neighbors
Researchers aren’t yet sure if it happens outside the lab. If it is the case, then it is another example of a life form having strategy that raises the question, “Could it really have randomly evolved with no underlying intelligence in nature?” Lot of those questions piling up.
Casey Luskin comments on the New Yorker article, Journey to the Center of Our Cells
It’s a sort of shift in perspective. The very fact that no one is rushing in with a reductionist explanation points to the significance of the shift. Researchers are pausing to observe and reflect for once.