origin of species?

Question

Among the species that produce by the process of mating (sexual intercourse between a male and female) my question is on the starting point. How the first male or female or both were born? If it was without mating why the process is required for all subsequent reproductions?

Answer 1

There are *many* different variations on sexual reproduction ... the variation with specialized male and female sexes is just the most familar because it's the one practiced by our species.

Even down to single-celled organisms that reproduce asexually, there is still often some exchange of genetic material (e.g. bacteria that exchange bits of DNA with each other ... and viruses, which are basically pieces of DNA or RNA that have gone "solo").

The main point is that this trick of exchanging DNA is a very good method of generating new genetic material, rather than having to wait for a lucky mutation. So organisms that have this trick are able to evolve faster in times of crisis (like a food shortage, or wild temperature fluctuations), and thus produce more organisms with this trick.

From the idea of organisms that exchange DNA *on occasion*, come the practice of it becoming more and more common, to the point where exchange of DNA becomes a common practice during reproduction. And sexual reproduction is born.

From there it is easy to see specialization of certain mechanisms of spreading DNA. In multicellular organisms, (where cells are already specializing in certain tasks), it makes sense for some cells to specialize in propagating DNA, while others are good for receiving DNA and beginning the development into the new organism. One is small and mobile (think pollen or sperm), and the other is larger and more robust (think seeds or egg cells). These early organisms all produce both kinds of cells, and develop specialized organs and systems for spreading them. These cells are just as likely to find and fertilize other cells from the same individual (basically producing clones), but they also find and fertilize cells from other individuals as well (especially if these cells are designed to travel well in water, wind, or other mechanisms).

In other words, the early forms of sexual reproduction, every individual is both male and female (has both kinds of parts, and makes both kinds of cells). This is still the system used by the majority of flowering plants.

Organisms can take this a step further and have stages in their development where they change between male and female, or combine sexual reproduction with asexual (parthenogenesis ... e.g. in aphids and some other insects). Eventually some individuals specialize *only* in making the small cells or the big cells, and we have dedicated males and females. Sometimes this can be determined by environment (as in bees, where the food fed to larva determine whether they become male, female, or neutral drones). Or this can be determined genetically (and even there, there are many different systems besides the XY system we use).

In summary, there wasn't a sudden leap from asexual reproduction to dedicated males and females ... there were many intermediate stages in between ... and many of these systems are still in use today.

Answer 2

There are still lots of examples of reproduction in all varieties present today in flora and fauna, with and with out male and female partner's. Same like Darwin's Galapagos birds developed on each island a specific beak for the available food, Reproduction techniques developed and still develop based on mutations and their chance of survival. There wasn't suddenly a monkey with male organs and a monkey with female organs. Reproduction techniques needed 100 of millions of years to develop and the basics are still the same as for the beginning of life, simple split and copy of DNA.

Answer 3

Here is a simple version of my non-expert opinion of how gender came about.

Before there was any gender, there was asexual reproduction, and budding etc.
Then, a mutation occurred in one organism which allowed the sharing of genetic material with other organisms. This allowed some diversity within the species, making it more robust in the presence of diseases etc. Hermaphrodites came into being.
Then, a mutation occurred which allowed one organism to share his genetic material with more organisms than other hermaphrodites, but he lost the ability to have offspring himself. But his genetic material was more widespread because of it, so his material became the predominant template for his species. This gave rise to different genders.

In this scenario, males came before females.

Just speculation, though.
.

Answer 4

i think of that is simply by fact if there is something that proves portion of their holy e book incorrect (such simply by fact the theory of evolution dismantling Genesis), then they understand that perhaps each thing else in the Bible ought to be puzzled. Then they think of this by some capacity invalidates their faith. i think of the real question is why somebody might base their faith on something so truthfully refuted. And for rationalization, not all religions have holy texts. In some religions, there are countless different aspects (alongside with in Hinduism) or that is going to possibly not even have any texts in any respect (one occasion being Druidism - it substitute right into a thoroughly oral custom).

Answer 5

the first male & female organisms were born of continous cell division.first a single cell was born which divided to produce bigger forms of animals and birds.and as for the latter part of the question ( if it was without......?) you can just go and ask your mom & dad about it.



and now please don't ask how the first cell came into being!!!!

Answer 6

...

I saw a science documentary once where some scientists
theorized that we all come from some other place in the
galaxy, or the universe. By way of a meteorite.


..

Answer 7

Bible : Genesis : Chapter 1.