Ecological niche partitioning between Anopheles gambiae molecular forms in Cameroon: the ecological side of speciation

Table 4 Summary of ecological and chromosomal divergence between molecular froms of An. gambiae in Cameroon.

	M form	S form
Ecological niche
*Fundamental niche*
Breadth	Limited, mainly restricted to the forest biome South of the country	Large, encompassing all biogeographic domains
Discriminant EGVs	Rainforest landscape, high Water Vapor Pressure, High rainfall, Proximity of permanent water bodies	Sunlight exposure, High temperature and evapotranspiration, "open" landscapes (savannas, croplands)
Overlap	Extensive overlap with S Limited overlap with An. arabiensis	Limited overlap with M Large overlap with An. arabiensis
*Realized niche*
Geographical distribution	Patchy	Continuous
Co-occurrence	Extensive sympatry with S Limited sympatry with An. arabiensis	Extensive sympatry with M (South) Extensive sympatry with An. arabiensis (North)
Chromosome-2 polymorphism
Level of polymorphism^a	Low (1/Σpi² = 1.71)	High (1/Σpi² = 7.41)
No. of karyotypes observed	12	29
No. of "private" karyotypes^b	1	18
Segregation of karyotypes along environmental gradients	Yes	Yes
Segregation of karyotypes in chromosomal clusters	Yes	Yes

^a 1/Σp_i²: chromosomal diversity index, where p_i is the frequency each karyotype in the population [72].
^b Number of haplotypes that were found in only one molecular form.

ISSN: 1472-6785