These brown tropical frogs have evolved switchblades: on each hand, just above the thumb, males have a sharp, retractable spine that is shaped like a scythe. The book also has an index, author's notes, and an extensive bibliography, making it a good resource to find specific information, or to find further reading on the subject.
However, as Olivia Judson explains, it is quite natural within its own context. What's wrong with me? But their glory is fleeting, For reasons that remain mysterious, the loss of sex is almost always followed by swift extinction. Even in species where the females store sperm for years, they only keep a few of the sperm that they get.
During sex, the penis often gets stuck. If not for sex, much of what is flamboyant and beautiful in nature would not exist. If you intrude into a bower and move things around, the artist will put them back again after you've gone. Remember, You won't find any rules -- not a one! Females come to the bowers to mate.
Tatiana, I'm a European praying mantis, and I've noticed I enjoy sex more if I bite my lovers' heads off first. So in species like yours or mine, where a male delivers his sperm personally, you would imagine that sperm counts would drop.
Pages with related products. Honeybees have sex on the fly: you take to the skies and mate with any male who can catch you. This simple process, discovered by Charles Darwin and Alfred Russel Wallace in the nineteenth century, is the principal mechanism of evolution. Dropping his bag, he turns into the dining room and stops short.
Males in many species are fiercely possessive of their mates.
How can I get him to quit? Apparently in response, the male has evolved pseudophallus—a rod of tissue that cannot transfer sperm, During sex, he rubs this rod against the female's genitalia for about half an hour—at which point he ejaculates from his genital opening. Your guess is as good as mine.
I found the jokey 'Dr Tatiana' conceit a bit confusing and unnecessary, but that just maybe because it was published in and that's not really amusing any more. To explain his results, Bateman appealed to what he saw as the essential difference between the sexes--that males produce lots of tiny, cheap sperm whereas females produce a few large, expensive eggs.