What and when was the first organism in evolution to have sexual reproduction (have a male)?
607312
I am not sure what you mean by uni-sex in biology....\n\nIn biology, sexual reproduction is not said to have been started with only females per se! Uni sexual is not the same as hermaphroditic either. Monoecious and dieocious are the usual terms. Monoecious means hermaphrodite and dioecious means separate sexes. But reproduction can be either sexual or asexual (and sometimes some organisms do both, like, mosses, liverworts, ferns with alternation of generations.) \n\nThere are a few species of animals who have only females, though....at least 22 species of parthenogenic lizards identified last I checked! They lay eggs, mate like "lesbian lizards" without sperm and have babies. Wild!\n\nHowever, a "male" is usually described in biology as any organism that makes "sperm" gametes, so in that case, hermaphroditic organisms like most flowering plants (sperm is in pollen) have males as PART of the often hermaphroditic flower known as the stamen.  (some flowers are dioecious) So males are found in plants or animals.  In fact the anther is the pollen producing part of the stamen and is sorta comparable to the testes of the animal. In fungus there are opposite strains of hyphae that reproduce "sexually" but not with gametes and they are described as + and - branches, which some claim are m-f, but it is still considered sexual reproduction, whereby genetic information is exchanged and a genetically DIFFERENT offspring is produced. Asexual produces gentically identical offspring-clones. Bacteria usually reproduce asexually, but sexual conjugation can occur (sexual) in bacilli. Paramecium are the most famous for their sexual reproduction-conjugation too. In the cases of fungi, bacteria, paramecia, however, the gender is not considered even though it is considered SEXUAL. So what biologists consider as very "primative" organism are capable of sexual reproduction.
279116
Several billion years ago, the first simple amino acids formed crude proteins and RNA to act as simple genetic coding. Over time, these nondescript organisms evolved into bacteria, then photosynthesizing bacteria. Eventually they evolved into simple invertebrates capable of sexual reproduction, and through tweaking of the ovulatory cycle, were able to lay fertilized eggs outside of their body. These invertebrates became fish, then amphibians, then reptiles, then birds. From those birds evolved the ancestor of the chicken which after 4 billion years of evolution was already capable of laying eggs.\n\nThe end.
525521
Female Reproductive System.\n\nDescription:\nThis is the human's reproductive system, that is capable of producing a new being to the world. This is situated in the female gender of any species. (But we do find certain exceptions like, Sea Horses, where the female sea-horse simply produces the eggs, yet hands them over to the male sea-horse to take care of! mostly mistaken to believe that male sea-horses do have a reproductive system.) Its the only natural way of reproducing a specific being to the world.(Their are other ways, to reproduce species, in a lab i.e. cloning, tube.) \n\nBenifit:\nReproduction of a specific specie would keep them away from the Red-Data-Book, where all the endangered species are listed.\n\nThis is a very basic explanation.\n\nHope it is helpful!\nGood Luck!
812776
First, we didn't all start out as Sperm - that's only half the equation.  We all started out when a  sperm and egg mixed.  That sperm and egg combined and then had all the genetic information to produce each one of us.  That genetic code determined, at that point in time, what each one of use would be (physically).\n\nThe genetic code of some sea animal does not have the ability to produce one of us, and there is no evidence to support the theory that the complex genetic code in any sea animal could mutate to produce one of us.
840584
good way to remember - mitosis happens in my toes - asexual reproduction of cells, otherwise known as growth.\n\nMeiosis is the process by which sexual reproduction occurs, as in a combination of gametes (containing half the necessary genetic material) to create a new cell.\n\nAlleles are portions of genetic material that have a physical (or phenotypic) effect. These are usually sections of chromosomes, bundles of colied and intertwined DNA.\n\nMutation is any alteration of the Deoxyribonucleic acid (DNA) or Ribonucleic acid (RNA). Evolution could not occur without mutation. Intelligent Design is a bunch of nonsense. It's all random and we are very lucky to be alive and sentient. Don't waste your intelligence on Yahoo Answers. I will now follow my own advice...
219004
In my opinon.. the first chicken egg pre-dated the first chicken.\n\nAt one point there was a creature that was only one mutation away from being it chicken - it was ALMOST a chicken.  It mutated and then laid an egg that expressed the mutation by hatching into the worlds first full fledged chicken.\n\nThis question can be argued so many ways...  of course, if you don't accept the theory of evolution, my arguement is meaningless.
370678
The first example would be "halpodiploidy" that occurs in bees, ants and wasps. In this form of asexual reproduction, females lay unfertilized eggs. The eggs can then hatch without fertilization, giving an asexually produced male, or they can be fertilized by a male, giving a sexually produced female.\n\nA second example would be "parthenogenesis" (Greek for "virgin birth"), seen in some fish, reptiles and amphibians. One commonly studied reptile species, the lizard Cnemidophorus neomexicanus, contains only females. All progeny contain the exact genetic information as its mother, essentially making it a clone. The females still engage in lesbian sexual behavior, which is thought to stimulate the laying of eggs. No genetic information, however, is transferred during this sexual act.\n\nThere are many other examples, and the previous answer touched on a few. I would add that anthrax is a bacterium, and therefore NOT a many-celled organism.
557531
EGG!\n\nThe cleidoic egg is a reproductive structure seen in reptiles way before the evolution of the ancestral birs (e.g. archaeopteryx, we're talking millions of years ago).  \n\nAs certain reptiles evolved into birds, the egg remained as their preferred method of reproduction and thus the egg we know today evolved.  \n\nSince reptiles had it before ancestral birds and chickens clearly evolved after ancestral birds, then the only logical rationale left is that the egg came before the chicken.
317556
Flower\nIf both sexes are in the same flower (and plant) then it is a HERMAPHRODITE\nIf not, then they will be female and male plants (of the same species)
1125070
In zoology, a hermaphrodite is an organism of a species whose members possess both male and female sexual organs during their lives. In many species, hermaphroditism is a normal part of the life-cycle. Generally, hermaphroditism occurs in the invertebrates, although it occurs in a fair number of fish, and to a lesser degree in other vertebrates.
812119
asexual reproduction doesn't require two partners in order to reproduce...sexual is the opposite.  It requires two creatures of the opposite sex in order to reproduce.
717215
What species of male?\n\nLimp or aroused?\n\nGotta be a little more specific here!
809779
1. b, because even if the father was heterzygous, there would still be a 3:1 ratio of brown eyed offspring\n2.d, autotrophs are organisms that produce their own food and do not need to  get nutrients from other sources\n3. True, I believe that fertilization occurs in all sexuallly reproducing species, but there are some organisms that reproduce asexually, but you may not be talking about those.\n4. False, There are asexual organisms that are eukaryotic
63835
Scientifically speaking, the egg must have come first because there was a non-chicken animal that evolved into a chicken, and the only way for that non-chicken animal to have evolved into a chicken is if there was a mutation during meiosis (reproduction). So the non-chicken animal would have laid an egg which became a chicken.
1133326
The hen, or the ancestors of the hen, had to come first. The mode of reproduction would have evolved later when the original mode of reproduction became dangerous to the parent's health, or just more convenient.\n(please don't flame me for this; most of the Theory of Evolution is proven to be true in that humans are taller than they were a hundred years ago, immune systems learn to fight off diseases, many different species have split from one, etc.)
399423
Snakes, lizards and amphisbaena (which most of you won't have heard of, but they're neat!) have "hemipenes", basically dual penises.  It has no real advantage, it's just how they evolved.  They only use one at a time.  It's just a different way to evolve a penis structure on a bilaterally symmetrical animal.
1137276
There are organisms (fungi, mostly) with more than two genders. We call these "mating types." A mating type can usually mate with individuals of all other mating types except its own type.\n\nSupposing there were many mating types at first, as rare ones get unlucky they go extinct, until there are only two left. These become male and female (if they have gametes of different sizes).