As a matter of technical fact, it's not GPS time that gets adjusted with leap seconds, it's UTC. From a user perspective in most cases the difference isn't particularly meaningful because you probably want to convert between GPS time and UTC and for that use case it doesn't matter whether you add or subtract the offset to one parameter or the other. But the satellites don't update the time they broadcast every so often to align with UTC. They've been counting seconds as accurately as they can since they started broadcasting. Instead, they broadcast, in the GPS navigation message, the offset, in integer seconds, from UTC. If you are reading time directly from a GPS message, you never have to worry about it repeating or skipping an increment. UTC technically could do either one of those.

E: to be clear, the GPS control segment routinely updates the clocks on the satellites to maintain synchronization tight enough to meet the GPS specified error budget, but these adjustments are transparent to users and never anywhere close to entire seconds

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I believe this is the article you are referring to. It has gotten a lot of publicity and is good for raising awareness.

However, this article explains that the main patterns affecting insect biomass (not abundance diversity) and in the discussion explains why the long-term study above may not account for larger effects, such as an increase in temperature in a historically mild climate. They specifically designate a subsection of the discussion to comparisons between the two studies.

edited for clarification

What exactly are you asking for? Are you asking for the range of irradiance under which humans can have "acceptable" vision, however you define that? Because if that's the case, it's going to vary by illuminating source. That is why you can't find convenient converters online. Stare at a light source that's putting out 100W in long range infrared and you can't see a thing, but your face will probably get warm if you're close enough. On the other hand, stare at a white LED that's putting out 100W across the visual spectrum and it's going to look pretty darn bright. Unfortunately, the luminous efficacy (how bright a light source of a particular wavelength appears to a human being given a certain amount of emitted flux) is variable based not only on wavelength but also on overall lighting conditions, because the sensors in your eye which are used at low light have different wavelength dependent response than the sensors in your eye that are used in brighter light.

Lux is the unit for radiative flux that is useful for human vision. It's the unit which is intended to reflect how bright a light source actually looks, without regard to how much total radiation is coming out of it. The range of human vision, in terms of being able to develop a useful visual picture based on the incoming light, is roughly 10^-5 to 10^+5 lux. If we make the further assumption that even at very low radiation power the eye is most sensitive to 555 nanometer wavelength light (which is not true) and use the conversion for luminous flux to radiative flux assuming that all of the light is monochromatic 555 nm light, we have 683 lux = 1 W/m^2. These edges aren't exactly precise, so let's just use 10^3 as the conversion factor between lux and watts per square meter, in which case we get a visual range of 10^-8 to 10^2 W/m^2.

Again, there's no single answer to your question. It's underdetermined. But as a general estimate the above is somewhat reasonable.

Wow thanks for the detailed answer! I am just barely too old to have received the chicken pox vaccine as a kid (my sister is 2 years younger and got it), so this is very interesting.

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i'd also like some. from what i know loss of habitat/agriculture/insecticides are the main reasons insects are on decline and ou didn't even mention those.

also f.e. for germany it's ~70% less insects over the last few years, which is unprecedented. why are you so sure their numbers will spring back?

(not an expert though)

This may be ad hoc, but I could see warmer temps being a signal for environmental instability, therefore more males equals more genetic variability (more alligators), giving the population a better chance of adapting.

Cooler temps, creating more females, so as to "lock in" certain traits into the population.

IMO, systems seem to fluctuate between "searching" patterns and "chasing" patterns; robustness and efficiency, community and hierarchy, public square and tower, or as the alchemists said: solve et coagula.

You see this too in society: certain segments of society seem to follow either r or k patterns. Poorer people have more children, less neoteny shorter lives, etc.

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There are extracellular adhesion molecules, expressed specifically at synapses, that promote and stabilize synapses. Some examples include ephrins, neuroligins, and neural cell adhesion molecules. Also, perineuronal nets also seem to promote synapse stability.

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Generally this is not a straightforward task, however if the uncertainties on the variables and the correlations between the variables are small, you can use a formula:

For a function f(x, y, z...), where x, y, z... have uncertainties σ*x, σy, σz..., the uncertainty of the function σf* is approximately sqrt((∂f/∂x)^(2)σ*x^2 + (∂f/∂y)^(2)σy^2 + (∂f/∂z)^(2)σz*^2 + ...).

You can see for simple cases that this produces sensible results. For example, for the case of multiplying a value by 6 to convert between volume per 10 seconds and volume per minute, we'd have f(x) = 6x. This gives us ∂f/∂x = 6, so σ*f* = sqrt(6^(2)σ*x^(2)), or σf* = 6σ*x*. Multiplying a value by 6, therefore, increases the uncertainty on it by 6 as well.

For another example, consider adding two variables, so f(x, y) = x + y. Then, ∂f/∂x and ∂f/∂y both equal 1, so σ*f* = sqrt(σ*x^(2) + σy^(2)). This is only an approximation based on assuming x and y are uncorrelated, if they are correlated then this isn't quite accurate (if they're correlated then σf* = sqrt(σ*x^(2) + σy^(2) + 2σxy*)), but the nice thing about this formula is you can use it in a lot of different situations.

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>However, they remain recessive for various reasons. This could include the recessive trait being advantageous in certain circumstances, but not others. Or that is only an advantage if other traits are also expressed at the same time

This makes no sense. "Recessive" described how an allele intersects with other alleles, and this is largely determined by the molecular mechanisms the protein produced by that allele is part of. A trait cannot change from recessive to dominant, no matter how advantageous or disadvantageous that would be. And while recessive traits are acted upon by evolution, that only happens in homozygous individuals that have two copies of that gene and thus show that trait. A newly-arising recessive mutation could spread through quite a few generations of heterozygous individuals, being passed on but not expressed, until two heterozygous individuals met and bred to make a homozygote. In the meantime, that allele could pick up new mutations that would change it's function without significant selection pressure.

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No I am saying the odds are lower than they stated which is true.

I am talking about the odds of any given mutation being advantageous not the odds of any member of a species eventually getting a beneficial mutation. I have no idea where you got that idea.

My background is in ant ecology, but I have had general entomology training. I can find some references for you in a few hours.

Edit for more compelling evidence:

a famous example of rapid evolution though, variation must exist for selection to act upon, so small populations are at greater risk given that they are likely to have much lesser genetic diversity.

Here is an example of mutualism breaking down as the result of environmental change (herbivore exclusion). While this is specific, it highlights that mutualisms once thought to be tightly bound may be more or less plastic, resulting in further change in community assembly, which is probably one step in a series.

I believe a major hurdle, explained best in this article, is that we simply do not know the full extent of insect diversity. The key points are that the biggest factor affecting insects is shared by plants and vertebrates alike: ecosystem change.

To return to the original question: are we past the tipping point? For insects as a group, they are super numerous and occupy a tremendous variety of niches. Insectes isn't going anywhere. Admittedly there is a cascade of declines are already in the works, similar to other vertebrate groups.

tl;dr - Reliable estimates of insect extinction are very hard to quantify at this stage, but the biggest factors causing decline in insect abundance are largely the same as those for vertebrates and plants. The best way to preserve that which we don't understand is not to change it in the first place.

No, but you're saying the odds are low, but in reality the odds are almost guaranteed. It's rare for an individual. Its certain for a species