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df= 31, P>0.05). However, the plot graph indicates that in waters shallower than 1000
m, generally species with large body sizes are found, from 1000 to 3000 m species of
all body sizes occur and at depths greater than 3000 m only species with large body
size are found (Fig. 4.4).
The correlation between depth and egg size was proved to be not statistically
significant (Spearman’s Rs= 0.136, df= 31, P>0.05) (Fig. 4.5).
The Spearman’s correlation coefficient showed that no significant correlation
exists between depth and Gonad Index (Rs= 0.297, df= 31, P>0.05). Therefore, these
reproductive features of the asteroids do not have a direct positive or negative
variation in relation to depth (Fig. 4.6).
The results of both Hierarchical cluster analysis and MDS showed species
clustering in three groups, according to maximum adult size, maximum egg size and
maximum Gonad Index (Figs. 4.7, 4.8).
The first group which was labelled as A contains 10 species which have small
adult size. Their major radius (R) ranges from 24 to 85 mm in length, the egg size is
large with diameters ranging from 546 to 1444 µm and low Gonad Index, which
values range from 2.11 to 5.59.
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