Submitted by PHealthy t3_11ebbka in askscience
AndrewFurg t1_jad9mp9 wrote
Not likely. Insects as a group are exceptionally diverse and most reproduce quickly with large numbers of offspring. It will vary strongly from group to group, with heat-loving generalists doing well and specialists (e.g. obligate parasites with rare hosts) hurting the most.
Additionally, some are very susceptible to pollution, while others can survive nearly anywhere (e.g. mosquitoes in shallow, ephemeral pools).
PHealthy OP t1_jadeqow wrote
Do you have any references or is this just a lay opinion? From what I've seen, not my field, it would seem fairly dire.
AndrewFurg t1_jadh7r4 wrote
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.
se_nicknehm t1_jadqa4v wrote
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)
AndrewFurg t1_jadtd1a wrote
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
lollroller t1_jaedxrw wrote
Not my field either, but it seems fairly obvious that insect numbers and diversity are considerably higher in warmer areas compared with colder regions, and are highest in the tropics.
Therefore it would seem that if anything, the insect population will increase
PHealthy OP t1_jaelldn wrote
Water, pollution, pesticides, encroachment/habitat loss, extreme weather....
A few things against a stable and prosperous environment.
lollroller t1_jaencos wrote
Nonsense, warmer climate = higher biodiversity, not lower. This is not debatable
Pesticides yes, pollution debatable; habitat loss not a problem, there is plenty of planet surface left; insect populations can and will shift easily, they won’t just stay in place and become extinct; and these obviously aren’t climate issues.
There are plenty more real problems to worry about
beaucoupBothans t1_jaerfyo wrote
It's a range and species have adapted to live in those ranges from desert to arctic. It is true that higher diversity is in temperate and tropical climates but that does not mean that rising temperatures in those zones will equate to even higher diversity or that increases in hot or colder climates will automatically equate to higher biodiversity. Most species have evolved to exist in the relatively narrow ranges to which they have adapted. Or have over millennia developed adaptations for ranges of temperatures like migration and hibernation. Changes in temperatures will affect these behaviors and affect diversity. We are already seeing this in marginal climates.
lollroller t1_jaetn36 wrote
Yes, but in general, warming will not eliminate niches, but rather shift them about, and not overnight neither.
Regarding whether the tropics will become more bio diverse, didn’t insect diversity peak during the Cretaceous, when the Earth was considerably warmer? So I think it is reasonable to think that this might actually happen.
beaucoupBothans t1_jaeuf9l wrote
Because it is not something that happens in the timescales we would need or want it to happen.
PHealthy OP t1_jaev06x wrote
And that rapid climate warming doesn't result in tropics, it results in deserts.
PHealthy OP t1_jaep2wd wrote
Right, I suppose you don't think there's an anthropocene mass extinction?
Read this:
lollroller t1_jaese3z wrote
No, I don’t think so. I’ve read that “article” before, but admittedly have not pursued the primary studies.
The meta-analyses they quote range from:
“In 2020, three large metaanalyses appeared, two of which focused on insects. The first, van Klink et al. (17, 18), examined 166 studies with demographic data spanning 9 to 80 y. Their assessment, driven largely by European and North American datasets, suggested terrestrial insects were declining at a rate close to 1% per year, while aquatic insects appeared to be increasing in abundance, again by about 1% per year.”
To:
“Crossley et al.’s (51) metaanalysis of insect demographic data (spanning 4 to 36 y) for 15 long-term ecological research sites across the United States, reported no evidence of a continent-wide decline of insect abundance.”
They repeatedly mention loss of habitat, while conveniently leaving out that the vast, vast surface area of the planet remains unaffected by humans. Of course human encroachment and loss of habitat have and will continue to cause populations to geographically shift, but I can see no reasonable mechanism by which it will cause insect species to become extinct, let alone cause mass extinctions.
Viewing a single comment thread. View all comments