青海沙蜥的生长及两性生长差异

The Growth and Growth Differences between Female and Male of Phrynocephalus vlangalii

为了研究自然生境中沙蜥的生长和两性生长差异情况,于2001～2002两年间对分布在四川西北部若尔盖地区的青海沙蜥(Phrynocephalus vlangalii)进行了6次标志重捕.结果表明:第一年8、9月出生的沙蜥到第二年的6月SVL、TL和BM都有显著的生长(p＜0.05),雌、雄个体的两性生长差异不显著(p＞0.05);第二年6月至8、9月间,雌、雄个体的SV、TL和BM都有快速的生长(p＜0.01),从7月份开始出现了两性生长差异(雌性的生长速度J于雄性)(p＜0.01);第三年的6月至8月间,雌性的SVL、TL和BM仍在快速生长(p＜0.01),而雄性的生长则不显著(p＞0.05),雌性的三个生长指标的生长量远大于雄性(p＜0.01),并且SVL和BM的生长量与第二年的同期生长量非常接近(p＞0.05);四年以后,雌、雄个体的SVL和TL的生长及两性生长差异都不再显著(p＞0.05),但是在体形大小上还存在极显著的两性异形(p＜0.01).在青海沙蜥的生长发育过程中,雄性的生长曲线近似'S'形,而雌性则是非'S'形.雌、雄个体的生长受季节和年龄的影响,造成雌、雄两性成长差异的主要原因是雌、雄个体对繁殖的能量投入不平衡.

During the years of 2001 and 2002, six times mark-recaptures were conducted on Phrynocephalus vlangalii, distributing on Zoig6 grassland, northwestern Sichuan to study the growth and the growth differences between female and male （GDFM） living in natural habitat. The results demonstrated juvenile （both male and female）, born in August or September the first year, grew slowly at same speed （p 〉0.05） before next June. In the second year, all P. vlangalii had significant growth （p 〈 0.01） from January to August, but GDFM appeared in July （male grew faster than female） （p 〈 0.01）. From January to August in the third year, the SVL, TL and BM of female grew faster （20 〈 0.01 ） than the male＇s （p 〉 0.05）. The GDFM of SVL, TL and BM were very significant （ p 〈 0.01）, and the female growth speeds approximate to that of the second year （p 〉0.05）. When P. vlangalii are old to four years, the growth of SVL, TL and the GDFM were not significant （p,〉 0.05 ）, but the difference of body sizes between female and male was still significantly different （p 〈 0.01）. If the influences of the errors from measures and the differences among individuals were eliminated, the male growth curves would be logistic or ＂Sigmoid-like＂, while the females＇ were not. The growth of P. vlang＇alii was affected not only by season and age, but the disequilibrium of energy investment on reproduction, which is the main reason for GDFM.