Amplexus
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As Amplexus ( lat. , Comprise looping around, embrace ') is the state of the grip of the female of anurans (and few urodeles ) by the male during the mating season , respectively. It is a clinging reflex and it serves to synchronize the process of spawning and sperm release into the water (external fertilization) .
Lumbar amplexus
In the phylogenetically primitive species of the suborders Archaeobatrachia and Mesobatrachia , the male clings with his arms in the hip or lumbar region of the female, i.e. in front of the female's hind legs - the so-called lumbar amplexus or inguinal amplexus . Only the male's throat and chest come into contact with the female's back (compare, for example, toad , common disc , common toad , clawed frog ).
Axillary amplexus
In the "modern" frogs ( Neobatrachia ; compare, for example, toads , tree frogs , real frogs ) the axillary amplexus is observed : the male climbs onto the back of the female in such a way that it clasps it behind the front legs. In order to have a better grip, many species develop heat calluses . Often the amplexus already occurs during the migration of the spawning grounds; the males can then be carried piggyback over land to the breeding waters. This has less to do with convenience and more to do with avoiding the competition from males that are often outnumbered.
Mismatches and skeins
During the mating season, the hormone-controlled brace reflex of the males is very pronounced, so that they often impetuously and unselectively try to grip any object that appears to be reasonably suitable in shape and size. It is not uncommon for mismatches between different species or even with objects such as driftwood or dead fish (compare also: pond claw ). Human fingers are also gripped and “hugged” with amazing clamping force when they are pushed under the male. The male can then be easily lifted out of the water and even then often does not release his grip.
In addition, sometimes large “balls” of several specimens clinging to each other arise in the water - this phenomenon can often be observed especially in the common toad that spawns in large societies . This can lead to drowning or suffocation of animals. In particular, the female, which is mostly helpless somewhere in the middle of the "knot", is affected. In order to keep obtrusive members of the sexes at bay within the spawning community, males have a "call to liberation", the function of which is presumably to point out their mistake to the clutching person. However, this only works within the same way - and even then not always.
literature
- Klaus Kabisch: Dictionary of Herpetology . VEB Gustav Fischer, Jena 1990, ISBN 3-334-00307-8 .
