Small Things Considered

To Not Get Lost in the Trees of Life (ToL)

by Christoph | Which picture comes to your mind if you think of the 'Tree of Life' (ToL) ? Maybe it's Ernst Haeckel's venerable oak tree ? Or is it rather Carl Woese's famous "three domains" phylogenetic tree ? Al­though highly abstract, the latter still resembles a tree with stem and branches, at least as much as does the famous "I think" sketch by Char­les Dar­win, on page 36 in his Note­book B. Read more →

Fine Reading: A Chalk Talk

by Roberto | As a means of communicating science, chalk talks can be extremely effective way to engage the audience. These days such pre­sen­ta­tions have become part and parcel of the interview process of those seeking academic jobs in the life sciences. As much as I love such chalk talks, that's not what I will discuss today. Rather, I want to bring to your attention a... Read more →

Why Be Intracellular and Be Motile?

by Elio | Why would a strict intracellular organism be motile? In the case of rickettsiae (and some not strict intracellular parasites such as the listeriae and shigellae), motility is carried out through the activity of the host's actin, apparently for the purpose of infecting adjacent cells. I am not talking about that, but rather I will consider here... Read more →

A Lakeside Tale

by Christoph Weigel | How small are bacteria ? And how big can they get as single cells ? For the lower end of the size scale, we know since the work of Jill Banfield's team that a multitude of ultra-small bacteria exist with a spherical diameters of ~0.25 µm and calculated cell vol­umes of ~0.009 µm³. Much larger are newborn cells of Escherichia coli  with a length of... Read more →

In the Beginning… there were Stromatolites

by Gillian Belk | Where can we find the first life forms on Earth? Although we do not yet know the exact microbes that managed to spin together some genetic information and make proteins, we do have evidence of life as far back at 3.5 billion years ago in what are known as stromatolites. Read more →

Old Enzymes Tell Stories

by Elio | Offhand, what can you say about the enzymes of the earliest cells? Surely, a few things pop up, for example, they were fewer in number and probably simpler than the ones we have now. They must have had fewer frills than the modern ones, which tend to have clear-cut tastes for substrates and... Read more →

Curioser and Curioser

by Elio | Curious indeed is an organism called Kakabekia barg­hoorn­ia­na. It is known to exist both as an ancient fossil and as a present-day cultivable creature. Just as curious is that it has been shuttled across the great biological divide, now to apparently having landed firmly in the eukaryotic camp. However, there still seems to be... Read more →

Accidental Complexity

by Christoph Weigel | You may wonder why you read the same motto twice in a week in STC but there's a reason. I will follow up Merry's recent post, her lucid description of in silico  and in vivo  experiments demonstrating that evolution can achieve complexity by small incremental steps if they confer... Read more →

Evolutionary Ways

by Merry Youle | Evolution skeptics point to complex biological features as evidence that the amazing intricacy of the biological world could not be the product of blind mutation. The de novo  creation of such com­­plexity, they argue, would require far too many coordinated mutational changes before the new form provided any fitness benefit. Thus, evolution simply cannot explain such apparent leaps. Evo­lutionists, beginning with Darwin, and continuing today, have posited that... Read more →

Who Dares Doubt The Decomposing Powers Of Fungi?

by David Lipson | Apparently, it is widely accepted that it took fungi 120 million years to figure out how to decompose woody plants. Hence lignin-rich materials accumulated along with the appearance of widespread forests in the Carboniferous Period, which led to huge coal deposits until white rot fungi finally caught up... Read more →