The post is about some female members of the species, who are powerful, independent and leading.
1. Lioness are believed to be best at hunting and more active than lions. They are more frequently spotted in groups for hunting in the forests.
2. Orca are the female hunting groups in the marine animals. They are matriarchal and act as leaders for their tribe.
3. Parthenogenesis is the phenomenon of production of young ones from the female gametes without fertilization. This is observed in about 80 taxon of fishes, lizards, reptiles and few birds. These females have capability of giving rise to young ones without their male partner.
I hope you liked this post. Do comment about any other such organisms.
The fact that about three fourth of Earth is covered with water in the form of oceans, seas, rivers, lakes etc. is known by all of us.
But, how these water bodies were formed and what is the source of this much amount of water on Earth is the major topic of controversies and debate for the scientists.
The oceans are significant domains of the Earth because the first life was originated in the oceans and it protected the first organic molecules and organisms from the meteoritic bombardment and UV radiations.
Various theories have been proposed about the particular topic but, none of those is universally accepted till now.
The major theories can be studied as follows:
1. Cometary Theory The present volume of the water of the oceans is 1.4×10²¹ kg. The theory stated that during the earlier days of the formation of Earth, it was hit by several comets. These comets were full of water and about 2.2- 8.5×10²¹ kg of water was supplied to the Earth. But, it was not possible that the comets actually hit the planet during its formation period so, this theory is not accepted.
2. Terrestrial Water Inventory This states that the source of water and other volatile substances (including water and carbon dioxide) is the interior of Earth. During the time when the planet was formed, the substances were degassed outside.
3. Volcanism This states that the major source of volatiles is the volcanic eruption which released a large amount of water and carbon dioxide into atmosphere.
4. Asteroids About 90% of the total water on Earth’s surface was brought to the Earth through asteroids which entered inside. This is proved by the fact that deuterium to hydrogen ratio of oceanic water is close to that of asteroids. But, the ratio was found to be slightly different in deeper regions of Earth indicating that there are other sources of water also, besides the asteroids.
5. Solar nebula It is the clouds of gas and dust left after the formation of sun. Scientist Jun Wu suggests that one or two water molecules out of the 100 water molecules on Earth were formed from solar nebula. When the Earth was formed, its upper surface comprised of a large amount of magma. The atmosphere was initially composed of the hydrogen and noble gases brought by the solar nebula.
Have you ever wondered🤔 why fireflies flicker? Why does water surface glows in dark? The reason is phenomenon of bioluminescence. Have a read:
Bioluminescence is the process through which light is produced and emitted by living organisms.
It is generally found in the aquatic marine organisms living in water columns, under deep sea, among corals etc. It also occurs in the fireflies.
Scientists believe that bioluminescence could be the most common way of communication on the planet because the phenomenon mostly occurs in deep sea, which occupies the major portion of planet!!
They have also discovered that the phenomenon of bioluminescence has evolved around 40 times in the course of evolution while rayfinned fishes alone have evolved about 27 times.
Lanternfish have a light emitting organ, photophores present at their belly, ventral surface and a light organ at nose acts as a headlight.
A biological clock controls bioluminescence in the dinoflagellate, Pyrocystis fusiformis i.e. after the sunset chemicals responsible for light emission are synthesized.
The phenomenon is known to be existing in 1,500 species of fish, bacteria, algae, sharks, sea stars, jelly fishes and crustaceans.
Some dinoflagellates form blooms on the surface of ocean giving reddish-brown colour to them. But, at night, they sparkle with the waves of ocean. Some of them are toxic to living system thus, given the name harmful algal blooms (HBA). When they are consumed by aquatic organisms, they fall ill or may die too.
The way bioluminescent organisms flicker is due to a chemical reaction occurring in their abdomen, a molecule called luciferin which reacts with oxygen to produce light. In some organisms, an enzyme called luciferase catalyzes this reaction.
Different forms of luceferin is present in different species.
Sometimes luciferin occurs in the form of photo-protein, which immediately lights up an organism in presence of calcium ions.
As bioluminescent organisms live deep under the ocean, lights of only smaller wavelength like, blue and green wavelengths of light reach our eyes when we observe them.
1. Protection from Predators- Squid release bioluminescent fluid to confuse predators.
2. Attraction of Mates- Some worms and crustaceans use bioluminescence to attract their mates.
3. Feeding- Some fishes create a lighted lure near their mouth to attract the prey.