Jun 26, 2025 10:28 PM
Cambrian explosion may have occurred much earlier than previously thought
https://www.eurekalert.org/news-releases/1089082
INTRO: The Cambrian explosion was an extraordinary phenomenon in the evolution of life on the planet that led to the emergence of many animal phyla and the diversification of species. During this period, some 530 million years ago, most of the basic body plans of organisms that have survived to the present day emerged. However, this great explosion of life that changed the evolutionary landscape on Earth may have occurred millions of years earlier than previously thought, a hypothesis now reinforced in a study published in the journal Geology.
This is a main conclusion of a new study that analyses the body profiles of organisms — symmetry, segmented bodies, exoskeletons, etc. — from around 545 million years ago by analysing trace fossils, which are the fossilized marks in rocks and sediments left by the activity of organisms in the past.
The authors of the article are the experts Olmo Miguez Salas, from the Faculty of Earth Sciences at the University of Barcelona, and Zekun Wang, from the Natural History Museum in London (United Kingdom)... (MORE - details, no ads)
Membrane or metabolism, which came first?
https://www.eurekalert.org/news-releases/1088606
INTRO: LMU researchers have demonstrated a possible mechanism for metabolic processes without cell membranes in water-filled pores.
Looking at life today, it is difficult to imagine how complex biological processes and structures could have developed from simple building blocks. All cellular processes and reactions appear to be closely interdependent and necessarily occur within a cell membrane. There is no known organism that deviates from this pattern. But how did it come about?
How does a cell membrane form without metabolism? Or conversely, how does metabolism arise without a cell membrane? This classic chicken-and-egg problem is addressed in a recent study published in Nature Physics by researchers from LMU professor Dieter Braun’s team.
In their article, the researchers show that simple heat flow across thin, water-filled pores can accumulate a wide variety of molecules with different chemical and physical properties, and allow these molecules to interact and form reactions in a confined space, even in the absence of a cell membrane. In this very simple protocell, there is a thermal gradient that takes over the functions of a cell membrane, but not yet any physical boundary between the reaction and the diluted water.
“Our investigations show that this simple physical mechanism, which would have been very common on early Earth, can perform many functions that would normally require a cell membrane,” says principal investigator of the study, Dieter Braun. The results suggest that heated rock pores could have been the natural setting in which biological cells emerged... (MORE - details, no ads)
https://www.eurekalert.org/news-releases/1089082
INTRO: The Cambrian explosion was an extraordinary phenomenon in the evolution of life on the planet that led to the emergence of many animal phyla and the diversification of species. During this period, some 530 million years ago, most of the basic body plans of organisms that have survived to the present day emerged. However, this great explosion of life that changed the evolutionary landscape on Earth may have occurred millions of years earlier than previously thought, a hypothesis now reinforced in a study published in the journal Geology.
This is a main conclusion of a new study that analyses the body profiles of organisms — symmetry, segmented bodies, exoskeletons, etc. — from around 545 million years ago by analysing trace fossils, which are the fossilized marks in rocks and sediments left by the activity of organisms in the past.
The authors of the article are the experts Olmo Miguez Salas, from the Faculty of Earth Sciences at the University of Barcelona, and Zekun Wang, from the Natural History Museum in London (United Kingdom)... (MORE - details, no ads)
Membrane or metabolism, which came first?
https://www.eurekalert.org/news-releases/1088606
INTRO: LMU researchers have demonstrated a possible mechanism for metabolic processes without cell membranes in water-filled pores.
Looking at life today, it is difficult to imagine how complex biological processes and structures could have developed from simple building blocks. All cellular processes and reactions appear to be closely interdependent and necessarily occur within a cell membrane. There is no known organism that deviates from this pattern. But how did it come about?
How does a cell membrane form without metabolism? Or conversely, how does metabolism arise without a cell membrane? This classic chicken-and-egg problem is addressed in a recent study published in Nature Physics by researchers from LMU professor Dieter Braun’s team.
In their article, the researchers show that simple heat flow across thin, water-filled pores can accumulate a wide variety of molecules with different chemical and physical properties, and allow these molecules to interact and form reactions in a confined space, even in the absence of a cell membrane. In this very simple protocell, there is a thermal gradient that takes over the functions of a cell membrane, but not yet any physical boundary between the reaction and the diluted water.
“Our investigations show that this simple physical mechanism, which would have been very common on early Earth, can perform many functions that would normally require a cell membrane,” says principal investigator of the study, Dieter Braun. The results suggest that heated rock pores could have been the natural setting in which biological cells emerged... (MORE - details, no ads)