to climate change because of their sensitivity to tem-
perature, short generation times, and high flight ca-
pacity. Observations of insect herbivory on an oak
lineage during Quaternary climate change indicates
that there was higher damage during warm and wet
periods (A Eskildsen, PCL Roux, RK Heikkinen, TT
Høye, WD Kissling, J Pöyry, M Wisz, M Luoto,
Dirzo R, Young HS, Galetti M, Ceballos G, Isaac
NJB, Collen B., 2014,). Consequently, it caused some
insects species population decrease. Moreover, the
consequence of its increase causes the insect abun-
dance decline to a deadly level. With the loss of in-
sects’ habitats and the reduction of food source, the
diversity of insects decreased. At present, previous
researches mainly focus on general researches. How-
ever, there are few papers focus on particular climate
characteristics.
In the past, rich insect abundance brings plenty of
benefits to human. Flowering plants attract not only
bees but also predatory and parasitic insects that pri-
marily feed on plant-feeding insects and supplement
their diets with pollen and nectar. For instance, spe-
cific flowering plant species, including shrubby false
buttonweed (Spermacoce verticillata), partridge pea
(Chamaecrista fasciculata) and white Pentas lanceo-
lata attract the Larra wasp (Larra bicolor), a parasite
of mole crickets in the southeastern United States
(Doi, H., O. Gordo, and I. Katano 2008). Besides,
some other insects can provide food to other animals,
or some particular species can capture pests avoid the
damage of crops. To protect the insect species is a
meaningful and crucial way to protect the food source
of the crops, and it also keep the biodiversity in a high
level. If human beings do not pay enough attention to
the insect abundance decrease, when their population
decline to a warning level, it will cause harmful con-
sequence to ourselves and the whole earth ecosystem.
Therefore, it is necessary to analyze the insect abun-
dance. This study discusses and compares the effects
of insect abundance in different climates including
polar climate, tropical rainforest climate, tropical sa-
vanna climate and marine climate.
2 IMPACTS OF CLIMATES
This study discusses four different types, which are
polar climate, tropical rainforest climate, tropical sa-
vanna climate and marine climate, climates’ corre-
sponding effects to the insect abundance.
2.1 Polar Climate
Polar climate, mainly located in northern part of Eur-
asia, America and Antarctic, is the typical climate in
the high latitude zone. Opposite to tropical rainforest
climate, polar climate is featured with severe cold
temperature as well as desiccation. Compared to trop-
ical and temperate zone, insects biomass in polar area
is apparently less, but it makes up more than sixty per-
cent in terrestrial animal diversity (Adam G.Dale,
2020) and can obviously affect polar ecosystem in
different ways. Unfortunately, compared to plant and
vertebrate, research about insects in polar climate are
not extensive (Emma Coulthard, John Norrey, Chris
Shortall, W. Edwin Harrisb, 2019). The most com-
mon insect species in polar climate are flies and mos-
quitoes.
While global warming is happening everywhere
around the world, temperature in polar climate has
risen three times than that in other regions (Hulde´n
L, Albrecht A, Itamies J, Malinen P, Wettenhovi J,
2000), causing serious trouble to the local ecosystem,
including insects. Insects are the indispensable part of
the polar climate food web, influencing plants and
vertebrates in various ways (Field CB, 2014, Fonty E,
Sarthou C, Larpinz D, Ponge J 2009). Faced with ex-
treme climate change, plasticity may be the most im-
portant factor for insects to deal with variable thermal
conditions (Forrest, J. R. K., and J. D. Thomson,
2011).
Firstly, global warming may help some insects ex-
pand their range of movement. The main reason is
that some insects species have high thermal plasticity
to handle extreme temperature (Franzén M, Johan-
nesson M. J, 2007), e.g., between 1992 and
1999,2002 and 2009, the range of 56 species of Finn-
ish butterfly have moved 54.5km northward (Geena
M. Hill, Akito Y. Kawahara, Jaret C. Daniels, Craig
C. Bateman, Brett R. Scheffers, 2021). Biting insects
have also expand northward (Gillespie, Mak , et al.
2019). While change on the range of different insects
species is different, such kind of dramatic change like
Finnish butterfly does not happen frequently (Geena
M. Hill, Akito Y. Kawahara, Jaret C. Daniels, Craig
C. Bateman, Brett R. Scheffers, 2021).
In addition, climate change in polar area have re-
sulted in the decline of insect abundance. At Zacken-
berg, North East Greenland, from 1996 and 2014,
seven of the fourteen muscid species have been found
to have a dramatic decline in their abundance, some
even decline more than eighty percent (Field CB,
2014) as shown in Fig. 1. Climate change is also a
factor in the extinction of some butterflies and moths