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Warwick University's e-nose technology has been around for quite a while: https://warwick.ac.uk/fac/sci/eng/research/impact/electronicnose/
As far as I understand their technology, they sample gas, and analyse it using a solid state CMOS device to generate a signature signal for particular compounds/mixtures. The devices have been used in a variety of ...
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NMR spectroscopy is a technology that is used to identify molecules. So-called "NMR spectra catalogs" document the spectra of various known compounds. Acquiring these spectra requires purified samples, expensive equipment, and time. In addition to making next-generations of this technology into something that would be practical for realtime "smelling", you'd ...
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The latest documentary I watched about the Meganeura (a giant Dragonfly from Pre-Cambrian) seems to confirm your intuition.
Based on experiments by John Vanderbrook at Midwestern University, with bugs in conditions A with less oxygen than current Earth atmostphere, and a 31% oxygen atmosphere in conditions B:
The bugs from group B were roughly twice bigger....
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To paraphrase an old saying, gene changes should be weighed not counted. There are a plethora of types of gene changes, and they vary by orders of magnitude in their impact. In particular, which genes are affected has a huge impact. Some point mutations (change in a single or a few nucleotides) can be lethal. On the other hand there are trisomies where an ...
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Unfortunately despite the impression given by the many poor explanations available (including the one you quoted), homologous is not a synonym for similar.
Homology is defined as the existence of shared ancestry1,2. Thus, structures being homologous simply means they had a common ancestor — i.e. homology is a relationship not a property of an individual ...
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This subject is actually both complicated and incompletely understood. For example, there is evidence that some enhancers don't result in loops at all — instead their influence travels along the chromatin to a nearby promoter.
You can think of enhancers as being staging areas where protein complexes that promote transcription are assembled. In some cases ...
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You need to define “gene” for your question to make sense. In humans, each individual has roughly 100 novel mutations (that neither parent had) (Human mutation rate revealed). However, those are not necessarily “new genes”, since many occur in non-functional DNA, even those that occur in functional regions may not alter any function, and even those that ...
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23andme uses DNA microarrays ("chips") to perform genotyping. These methods only assay a set of previously known single nucleotide variants, so the probability of missing some specific variant (false negative) is high if that variant is not specifically assayed. It is not quite 100% as frequently known variants missing from the chip are closely associated ...
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Some genetic changes occur too fast for selection to take place.
Can you please define "genetic change"? Selection can only change the frequency of alleles in a population. It cannot make a new mutation. If by, "genetic change", you mean "mutation", then selection just can't do it. If by "genetic change", you mean change in allele frequency, then the change ...
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IanC's answer is great, but is missing one and possibly the most important point. There is a distinction between being alive or having life, and "life" in the sense that we associate with words like individual, personhood, being. In the first sense; the biological sense, a zygote is most definitely alive; a living thing; a lifeform etc. But in the second ...
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The discussion of when a life starts is a little more complicated than that. Many views and disagreements between them fuel the discussions of pro-life/abortion groups.
Some of the views and what they consider the beginning of life:
Metabolic view: Considers that there's no singular developmental moment that marks the beginning of life. Any single or ...
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