frog spawning – here is a collection of hundreds of eggs, which will bring dozens of tadpoles, which at the end usually only a handful of fully-grown frogs. More on class instead of mass, the tree, however, Steiger-frogs of the species Ranitomeya imitator in the Peruvian rain forest. The female lays one or two eggs in tiny ponds between the leaves of bromeliads. The young hatches, the male comes over and carries the tadpoles on his back to the next larger bromeliads Pool. Occasionally, the female brings a tasty Snack: a few unfertilised eggs.
A genetic signature for monogamy
It is a complex brood care, males and females need to work closely together. But as such a close pair bond? What genes, what hormones and neuropeptides are for this social monogamy responsible? To find out, has examined a group of researchers led by Hans Hofmann of the University of Texas in Austin five pairs of closely related monogamous and non-monogamous species of vertebrates. The result, published in the journal "PNAS": There seems to be a "universal mechanism", a genetic signature of monogamy in vertebrates.
The researchers collected brain tissue of closely related monogamous and non-monogamous species and measured the activity of certain groups of genes, including those that regulate social behavior. They compared about those two-point poison dart frog with Strawberry frogs Oophaga pumilio, does not live monogamous. Or the pair of image water Pipits Anthus spinoletta with the dunnock Prunella modularis, as well as faithful and less faithful voles, cichlids, as well as deer and whitefoot mouse.
influence on brain development and signal transmission
As a socially monogamous species are referred to, in which females and males of a pair bond deal, territorial behavior, and mostly, together with the offspring to raise. Longer researchers know that this is a complex and by species to species-varying behavior of materials at least partially of neurotransmitters such as Oxytocin and arginine-Vasopressin (AVP) is controlled. On receptors, the docking, then the reactions of the nerve cells in the brain. About these substances, the researchers found 24 genes, whose activity (or inactivity) with the monogamous behaviour of vertebrate animals in connection can be brought. The genes play roles in the development of the brain, the signaling from cell to cell, the control of nerve contacts (synapses), as well as for Learning and memory formation.
This means that species from four different vertebrate classes – fish, amphibians, birds, mammals – at least in part, to the same evolutionary ancient and well-preserved groups of genes, and to develop the brain and affect the animals behavior to be monogamous.More about
poison dart frogs are Resistant to their own poisonSascha Karberg
And before anyone asks: to what Extent is the research relevant for the more or less exclusive or inclusive of mating and reproductive behaviour of the people (after all, even a vertebrate animal), the researchers let not a single syllable.