Genome size variation is associated with life‐history traits in birds

Abstract

Genome size markedly displays variation across taxa. Genome size variation is affected by two principally different mechanisms (such as whole‐genome duplication events (polyploidization) and accumulation of noncoding elements). In addition, genome size variation is also affected by the phylogenetic signal, life‐history traits and environmental factors. Here, we studied the relationships between genome size and life‐history traits (e.g. clutch size, hatching time, fledging time, age at sexual maturity, longevity and body mass) among 240 species of birds using a phylogenetic comparative analysis and path analysis. We found that genome size was positively correlated with both body mass and hatching time. We also found that body mass was positively correlated with hatching time, age at sexual maturity and longevity in birds. Our findings suggest that although genome size was directly linked to body mass, evolution of larger genomes was also associated with larger bodies by the prolonged hatching time.

Genome Size Covaries More Positively with Propagule Size than Adult Size: New Insights into an Old Problem

“…Variation in genome size is often (but not always) associated with changes in various life-history traits, including not only propagule size and number, but also growth rate, duration of developmental periods, and age at sexual maturity ([ 8 , 9 , 10 , 11 , 15 , 16 , 19 , 32 , 48 , 57 , 58 , 59 , 60 , 80 , 97 , 103 , 109 , 113 , 177 , 186 , 189 , 192 , 195 , 255 , 293 , 294 , 308 , 309 , 310 , 311 , 312 , 313 , 314 , 317 ]; see also sources cited in Table 2 ; but for contradictory evidence, see [ 97 , 98 ]). Interspecific correlations between genome size and longevity have also been proposed [ 48 ], but questioned [ 9 , 97 ]. Experimental manipulations of genome size (ploidy) provide critical evidence that genome size can affect life-history traits (e.g., [ 166 , 195 ]; also see sources cited in Table A2 ).…”

“…Artificial selection experiments may be especially valuable in this respect (e.g., [ 345 ]). Several investigators have emphasized that multiple causal pathways are likely involved in the evolution of genome size (e.g., [ 7 , 8 , 90 , 97 , 183 , 186 , 327 ]).…”

The Evolutionary Patterns of Genome Size in Ensifera (Insecta: Orthoptera)

“…The genome size of different organisms varies dramatically, spanning more than 200,000fold among eukaryotes (Gregory, 2001) and with at least 7,000-fold variation among animals (Dufresne and Jeffery, 2011). Genome size has a major impact on a range of fitness-related parameters such as growth, metabolism, life history traits, and for many species also body size (Dufresne and Jeffery, 2011;Alfsnes et al, 2017;Yu et al, 2020). Universally, an increase in genome size is concomitant with an increase in cell size, confirmed in almost all biological groups (Mirsky and Ris, 1951;Horner and Macgregor, 1983;Cavalier-Smith, 1985;Gregory, 2000Gregory, , 2002aGregory, , 2005aHardie and Hebert, 2003).…”

Genome size versus geographic range size in birds

“…For instance, a larger genome size may be an adaptive strategy, because it may directly or indirectly increase the nuclear and cellular volume ( Cavalier-Smith, 1978 ) and body size ( Gregory, 2005 ), buffer fluctuations in the enzyme concentrations, or protect the coding DNA from mutations ( Hsu, 1975 ; Janssen, Colmenares & Karpen, 2018 ). Likewise, genome size is correlated with cell cycle complexity ( Gregory, 2002 ; Yu et al, 2019 ), basal metabolism ( Vinogradov, 1997 ), tissue differentiation, and developmental rate ( Sessions & Larson, 1987 ; Xia, 1995 ; Wyngaard et al, 2005 ). Arnqvist et al (2015) showed that females with larger genomes laid more eggs and males with larger genomes fertilized more eggs in beetles.…”