New Visions in Biological Science Vol. 9

Forty-two studies on fire millipedes are reviewed to elucidate the mechanisms of selection; sperm competition and cryptic female choice were studied. Approaches to: (1) quantify size dimorphism and find the selection pressures operating on the sexes, (2) determine the functional significance of male and female genitalia, (3) understand why there should be a conflict of sexual interests in prolonged copulations, and (4) resolve the mechanisms of sperm competition and cryptic female choice in comparing male mating strategies to female mating strategies and sperm usage were included. The sexual differences between male and female body plans which are observable in millipedes may be biologically significant.

Sexual Size Dimorphism (SSD) in the diplopod genus Centrobolus has a positive correlation with body size. Size criteria are useful for determining species of Spirobolida diplopods. Length, width, and rings are the main components of interspecific variation in diplopod species. Interspecific variation in size was calculated in 6 species and data sets were tested for normality. All data observed and tested were normal. The objective was to quantify and compare intersexual variation (coefficients of variation) in length and width in 9 species using MEDCALC®. In C. digrammus, C. inscriptus, and C. silvanus there was a significant directional selection for slender males.

The Tropical Conservativism Hypothesis and Biogeographical Conservativism Hypothesis were tested in forest millipedes. Biogeographical Conservativism Hypothesis which suggests the processes invoked are not intrinsic to the tropics but are dependent on historical biogeography to determine the distribution of species richness. Latitudinal diversity gradient (LDG) was measured in the genus Sphaerotherium to distinguish between the two hypotheses. There was a significant correlation between the number of species and latitudinal degrees away from the equator (r=-0.8701, r²=0.7571, n=46, p<0.00001). An evolutionary preference for temperate environments appearing to have led to climatic constraints on dispersal based primarily on precipitation seasonality gradients was suggested.

Of the determining factors of copulation duration across arthropods, I reviewed copulation duration variance in forest millipedes. The objective was to calculate the variance in copulation duration. The null hypothesis was mean copulation duration and copulation duration variance were independent of body mass. Copulation duration and standard deviation squared for 4 populations of millipedes were seen in the literature. Copulation duration correlated with it’s variance (r=0.95, r²=0.90, n=5, p=0.01). Durations ranged from C. anulatus (34.9 minutes) to C. inscriptus (303 minutes) Female mass was correlated to copulation duration variance (r=0.95, z-score=1.86, n=4, p=0.03). Millipedes were similar to some arachnids where the duration of copulation and variance in copulation duration correlated with intra-specific size variation. Female mass correlated to copulation duration (r=0.99, z-score=2.71, n=4, p<0.01). Sexual size dimorphism (SSD) was related to male mass (r=-0.97, z-score=-2.17, n=4, p=0.01). Prolonged copulation duration was interpreted to have correlated with the intensity of sperm competition and female control of copulation duration. Females control the duration of copulation based on mass.

Of many determining factors of copulation duration across arthropods, I reviewed copulation duration variance in mate-guarding worm-like millipedes. The objective wass to calculate copulation duration allometry in worm-like millipedes. The null hypothesis was mean copulation duration and copulation duration variance were independent of body mass. Copulation duration and standard deviation squared for 20 populations of millipedes were obtained from the literature. Copulation duration was strongly correlated with variance (r=0.87, Z score= 5.74, n=21, p<0.01). These ranged from Gigantowales chisholmi (0.09) to Alloporus uncinatus (Mazowe-Hwange) (4238.01) and included some forest species (C. anulatus, C. inscriptus, C. ruber). Copulation duration variance was correlated to female mass (r=0.68, Z score=2.89, n=15, p<0.01). Copulation duration variance was correlated to male mass (r=0.80, Z score=3.85, n=15, p<0.01). There was no significant difference between these correlations (z=-0.67, n=15, 15, p=0.50). Copulation duration was marginally correlated to male mass (r=0.40, Z score=1.55, n=16, p=0.06). Copulation duration was not correlated to female mass (r=0.33, Z score=1.22, n=16, p=0.11). There was no difference between these correlation coefficients (z=0.23, n= 16, 16, p=0.82). Prolonged copulation duration was interpreted to have correlated with the intensity of sperm competition and inversely related to size when intraspecific variance in copulation duration were controlled (equal). Males control the duration of copulation based on mass and intensity of sperm competition.

The forest genus of diplopods belonging to the order Spirobolida found along the eastern coast of southern Africa was tested for size correlations. Four morphometric factors for male and female lengths (mm) and widths (mm) were extracted from literature and checked for correlations with each other using the Pearson Correlation Coefficient Calculator. Positive correlations were found in an analysis of 22 species of Centrobolus. Strong positive correlations between male and female lengths and widths were found. There was a moderate positive relationship between female length and male width (r=0.72, Z score=3.91, n=22, p<0.01). There was a positive relationship between male length and female width (r=0.62, Z score=3.16, n=22, p<0.01). Male length/female length correlation differed from male length/female width correlation (z=1.93, n=22, 22, p=0.05).

A forest species of millipede belonging to the Order Spirobolida found along the eastern coast of southern Africa were tested for size assortative mating. The objectives control for SSD in multiple mating to test for size advantages in mating. The male length was positively related to the duration of the first mating (r_s=0.30, n=46, P=0.04) but negatively related to the duration of the second mating (r_s=-0.35, n=46, P=0.02). Male length and copulation duration were different in first compared to second matings (z=3.13, n=46, 46, p<0.01); when female width (z=-0.59, n=46, 46, p=0.60) and SSD (z=-1.08, n=46, 46, p=0.28) were controlled. A mating order effect from positive to negative size advantage in mating was explained as a result of female choice based on male lengths.

Diplopoda resembled the majority of invertebrates where Sexual Size Dimorphism (SSD) was reversed. The objective: SSD was to be investigated in the genus Sphaerotherium. Male and female morphological data were obtained from the literature; this included male and female width, volume, and SSD for S. cinctellum, S. commune, S. compressum, S. punculatum, S. spinatum, S. tenuitarse, and S. tuberosum. Linear regressions were performed between the five morphological variables and latitude, precipitation, and temperature. SSD was strongly correlated with precipitation (r=0.76, Z score=1.97, n=7, p=0.02); related to the mating system, seasonality, and oviposition. Female width was related to temperature (r=0.75, Z score=1.93, n=7, p=0.03); related to fecundity selection. SSD was marginally related to temperature (r=0.61, Z score=1.42, n=7, p=0.08).

The objectives of this study were to determine what happened when Bergmann’s Rule meets Rensch’s Rule Sexual Size Dimorphism (SSD) and body size changed with eco-geographical factors. Latitude, longitude, precipitation and temperature were correlated with body size and SSD in the forest millipede genus Centrobolus. There were significant positive correlations between SSD and longitude (r=0.37, Z score=1.71, n=22, p=0.04), precipitation (r=0.29, Z score=1.28, n=22, p<0.10) and temperature (r=0.34, Z score=1.49, n=22, p<0.07). There was a significant correlation between SSD and latitude (r=-0.44, Z score=2.05, n=22, p=0.02). Eco-geographical variance in the polygynandrous reproductive systems occur with larger females and higher SSD occurring in warmer, wetter north-eastern habitats.

Eco-geographical rules maintained within a taxonomic clade, populations and species of larger size were found in colder environments, and species of smaller size were found in warmer regions. The objective was to test Bergmann's rule. It was tested in the millipede genus Centrobolus with reversed sexual size dimorphism (SSD). Two factors were measured from 22 Centrobolus species - body lengths (mm) and widths (mm). Longitude correlated with female length (r=0.46, Z score=2.15, r²=0.21, n=22, p=0.02), female width (r=0.41, Z score=1.91, n=22, p=0.03), male length (r=0.43, Z score= 2.01, n=22, p=0.02) and male width (r=0.28, Z score=1.27, n=22, p=0.10). Female volume correlated to longitude (r=0.29, Z score=1.31, n=22, p<0.10). The smaller species (C. digrammus) occurred westerly (18.4°E) while larger species (C. inscriptus and C. anulatus) were easterly (31.7°E). In between these two longitudes all the medium sized species ranged. Mean annual temperature from type localities correlated with body size. There was a correlation between species size and temperature (r=0.55, Z score=2.69, n=22, p<0.01). There was a positive correlation between female size (volume) and temperature (r=0.49, Z score=2.31, n=22, p=0.01) and male size and temperature (r=0.48, Z score=2.26, n=22, p=0.01). There were positive correlations between male length (r=0.57, Z score=2.79, n=22, p<0.01), male width (r=0.42, Z score=1.94, n=22, p=0.03), female length (r=0.57, Z score= 2.79, n=22, p<0.01) and female width and temperature (r=0.49, Z score=2.31, n=22, p=0.01). As terrestrial arthropods, size increases an order-of-magnitude with temperature in these univoltine arthropods. This was a converse Bergmann clade in agreement with latitude-size trends in terrestrial arthropods.

The objective of the present study was to test the Tropical Conservativism Hypothesis and Biogeographical Conservativism Hypothesis in forest millipedes. Latitudinal diversity gradient (LDG) was measured in the genus Centrobolus to distinguish between the two hypotheses. There was a significant correlation between the number of species and latitudinal degrees away from the equator (r=-0.91, r²=0.83, n=35, p<0.01). An evolutionary preference for temperate environments appearing to have led to climatic constraints on dispersal based on precipitation seasonality gradients and predation was suggested.

The Tropical Conservativism Hypothesis suggests processes of speciation, extinction, and dispersal resulted in higher species richness in the tropics and declined away from the equator. Biogeographical Conservativism Hypothesis suggests that the processes invoked are not intrinsic to the tropics but were dependent on historical biogeography to determine the distribution of species richness. 117 valid species were identified as belonging to the family Dalodesmidae with the objective to test the two hypotheses. There was a significant correlation between the number of species and latitudinal degrees away from the equator (R=-0.79, R²=0.62, n=116, p<0.01). An evolutionary preference for temperate environments appearing to have led to climatic constraints on dispersal based on precipitation/temperature seasonality gradients and predation was suggested.

The size of Juliformia has two main components, body diameter and the number of rings. The objectives were to study latitude and precipitation correlations with body rings and sexual size dimorphism (SSD) in Centrobolus. There was a significant correlation between the number of body rings in females and latitude (r=-0.53, Z score=-2.35, n=19, p<0.01) and body ring number in males and latitude (r=-0.41, Z score=-1.74, n=19, p=0.04). There was a significant correlation between the number of body rings in females and precipitation (r=- 0.60, Z score=-2.76, n=19, p<0.01) and body ring number in males and precipitation (r=-0.60, Z score=-2.76, n=19, p<0.01). There was a marginal difference between the number of body rings in males versus females (W=22.5, Z=-1.61, n=19, p=0.05); females had more rings. Anamorphic increase in the number of body rings at higher latitudes (South) is linked to lower precipitation and not temperature.

Diosgenin, a steroidal saponin spotted in legumes and yams, has been used for the treatment of a multitude of disorders like leukemia, inflammation, hypercholesterolemia and cancer. Besides being a lactation aid, it has been proven as a gastro- and hepato-protective, anti-oxidant, anti-diabetic and Vaso-dilatory compound. It is also a precursor for the production of several steroidal hormones. Hence, with this background, this chapter focuses on diosgenin’s pharmacological assets which evidently supports its clinical therapeutic implementation.

Sundarbans is recognized as highly productive ecosystems providing large quantities of organic matter to adjacent coastal waters in the form of detritus and live animals. With each passing year, Sundarbans is facing serious threats and hence need to be conserved. Phytoplanktons are the major contributors to primary productivity in this region. However, for broader economic benefit, employment and restoration of balance in the ecosystem, phytoplankton estimation is essential. This requires, proper knowledge of phytoplankton diversity and primary productivity which will help in future management and planning issues of the Sundarbans. This review conglomerates information from different phytoplankton-based studies that have been carried out from the Sundarbans mangrove ecoregion emphasizing on seasonal variation, hydrobiological parameters and molecular approach. It can be seen that among the diverse group of phytoplanktons, Diatoms are the most dominant entities in this region. Although the timespan is too short for predicting the impact of aquatic climate change, still variation in the phytoplankton community in the past few years indicates them to be potential aquatic bioindicators of climate change.

The River Nile branches into irrigation canals, which extends for many kilometers (40 km to 85 km), where each represents a semi-independent ecosystem. Of those, Bahr Shebeen (BSC) and Alkhadraweya (KHC) Canals are present in the Minufiya Governorate, and extend through out other governorates in the Delta of Egypt. Water Quality data included the following parameters: total hardness, total dissolved solids, electrical conductivity, dissolved oxygen, pH, Cl, Mg, Ca, Zn, Mn, PO 4, Fe, NO3, and Cu. These parameters were examined and discussed, for significant relationships for each Canal. The favorability of each ecosystem for fish was examined, on the basis of fish growth, gonad stomach somatic indexes, where BSC was found to be more favorable by 13 to 15%, for fish. Subsequently, Water Quality Index (WQI) was discussed for those Canals, and a simple WQI is suggested.

The objective of the study was too evaluated of the routine use of a commercially and naturally improvement of soil quality of ponds. So, nitrogen, phosphorus, potassium in the year of experiments was in no way unfavorable for the growth of the carps. Bacteria can be found in fresh water, soil, air, and seawater. Bacteria differ in their nature depending on their environment. Thus periphyton bacteria has different characteristic in different zone. But the study discussed about soil analysis in fresh water ponds in Sabang block areas. The study carried out for about one year in Sabang block areas. Soil gathered in a bucket. This soil was collected from five ponds in Sabang block areas (Ghat pond, Dhara pond, Majari pond, Nandan pond, and Masanta pond). There were two kinds of pond: control pond and experimental pond. The semi-dried cow dank was added to this pond. In this experiment, we used a few different methods. The AOAC standard methods were used to analyse the pond bottom soil for nitrogen, available phosphorus, and available potassium (1980). However, the nitrogen level in all of the experimental ponds increased significantly after treatment. Phosphorus plays an important role in increasing pond productivity. Potassium is not a limiting factor and is not required to increase output. Future scope is free hygienic fishes production in ponds.

The present investigation was conducted to determine the effect of stream habitat structure and physico-chemical variables on the diversity of insect community from a headwater stream of the holy river Pamba in the Western Ghats. Assessment of habitat variables, analysis of Physico-chemical parameters, and collection of both aquatic and riparian insects from the respective stream stretch were carried out from January to December 2019 on monthly basis.  A total of 25 species of insects belonging to six orders, 14 families, and 20 genera were reported from the headwater stream in the Western Ghats. Deep pools, boulder undercuts, overhangs, aquatic macrophytes, and leaf litter formed the habitat features available to the aquatic communities. The substrate composition and stability affected the positioning, movement, and feeding activities of the insect communities in the stream channel. The pH of the stream water was recorded at 6.02±0.21, 6.65±0.05, 6.47±0.4 during summer, monsoon, and winter respectively, which is optimal for the growth of the insect community. The summer is noted with an increased air temperature of 34.9±1.34^oC and showed high Lepidopteran abundance. The highest Dissolved Oxygen (DO) content in the stream water was recorded during the Monsoon period (9.2±1.54 mg/L). The healthy stream supported a rich insect community, which showed population fluctuation on a seasonal basis. The stream habitat with its rich riparian buffer contributes to the breeding and feeding sites of the entomofauna; also supports many endemic and migrant Lepidopterans.