Termites have a bad reputation. Most think of them as pests, a status that isn't helped by their recent reclassification into the cockroach family.
Plants & Animals
Sep 5, 2024
0
53
When the hot summer weather kicks in you may find yourself feeling concerned about furry pets and other animals we live close by to. But fur and hair are ancient adaptations that allowed human ancestors to develop more active ...
Paleontology & Fossils
Sep 4, 2024
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0
In the face of threats from other groups, humans, chimpanzees, and a selection of other species get closer to their own. Now an international team led by Kyoto University has shown that even our more peaceful cousins, bonobos—who ...
Evolution
Aug 23, 2024
0
124
According to a new study, as of April 2021, US Congress members whose ancestors enslaved 16 or more people had a net worth that was five times higher than that of legislators whose ancestors did not have slaves. Neil Sehgal ...
Economics & Business
Aug 21, 2024
4
190
The identification of a key gene in monotremes has increased our understanding of why the stomachs of platypuses and echidnas are atypically small, non-acidic, and, in the instance of platypuses, lack a pyloric sphincter.
Plants & Animals
Jul 23, 2024
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104
Plants have long been known to release chemicals to respond to stress and relay information to their neighbors. A team of scientists from Bigelow Laboratory have shown that glaucophytes, a small group of single-celled algae ...
Ecology
Jul 2, 2024
0
88
An international research team from Swansea University and UBC Okanagan (UBCO) has uncovered a new insight into human evolution by comparing humans' hearts with those of other great apes.
Evolution
Jun 14, 2024
3
188
Giraffes, with their distinctive body shape and variations in coat patterns, have long been an example in evolutionary biology teachings. They are a textbook example of how species adapt to their surroundings and survive ...
Plants & Animals
Jun 1, 2024
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1
Scientists at the University of Oregon have discovered that colonies of gelatinous sea animals swim through the ocean in giant corkscrew shapes using coordinated jet propulsion, an unusual kind of locomotion that could inspire ...
Plants & Animals
May 16, 2024
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1
Even though there is evidence of certain self-medication behaviors in animals, so far it has never been known that animals treat their wounds with healing plants.
Plants & Animals
May 2, 2024
1
505
An ancestor is a parent or (recursively) the parent of an ancestor (i.e., a grandparent, great-grandparent, great-great-grandparent, and so forth).
Two individuals have a genetic relationship if one is the ancestor of the other, or if they share a common ancestor. In evolutionary theory, species which share an evolutionary ancestor are said to be of common descent. However, this concept of ancestry does not apply to some bacteria and other organisms capable of horizontal gene transfer.
Assuming that all of an individual's ancestors are otherwise unrelated to each other, that individual has 2n ancestors in the nth generation before him and a total of about 2g+1 ancestors in the g generations before him. In practice, however, it is clear that the vast majority of ancestors of humans (and indeed any other species) are multiply related (see Pedigree collapse). Consider n = 40: the human species is more than 40 generations old, yet the number 240, approximately 1012 or one trillion, dwarfs the number of humans that have ever lived.
Ignoring the possibility of other inter-relationships (even distant ones) among ancestors, an individual has a total of 2046 ancestors up to the 10th generation, 1024 of which are 10th generation ancestors. With the same assumption, any given person has over a billion 30th generation ancestors (who lived roughly 1000 years ago) and this theoretical number increases past the estimated total population of the world in around AD 1000. (All of these ancestors will have contributed to one's autosomal DNA is concerned: this excludes Y-chromosomal DNA and mitochondrial DNA.)
Some cultures confer reverence to ancestors, both living and dead; in contrast, some more youth-oriented cultural contexts display less veneration of elders. In other cultural contexts, some people seek providence from their deceased ancestors; this practice is sometimes known as ancestor worship or, more accurately, ancestor veneration.
This text uses material from Wikipedia, licensed under CC BY-SA
