Lizard Moms Choose the Right Genes for the Right Gender Offspring

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The male of this species can be two to three times the mass of the female, but the females seem to be in control of the genetic destiny.

Two Dartmouth biologists have found that brown anole lizards make an interesting choice when deciding which males should father their offspring. The females of this species mate with several males, then produce more sons with sperm from large fathers, and more daughters with sperm from smaller fathers. The researchers believe that the lizards do this to ensure that the genes from large fathers are passed on to sons, who stand to benefit from inheriting the genes for large size.

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Giant Panda Genome Reveals New Insights Into the Bear’s Bamboo Diet

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A panda eats a large bamboo stalk.

A Chinese-led team including international researchers with a scientist from Cardiff University, has shed new light on some of the giant panda’s unusual biological traits, including its famously restricted diet.

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Canine Morphology: Hunting for Genes and Tracking Mutations

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Researchers studying the dog genome have a new understanding of why domestic dogs vary so much in size, shape, coat texture, color and patterning.

Why do domestic dogs vary so much in size, shape, coat texture, color and patterning? Study of the dog genome has reached a point where the molecular mechanisms governing such variation across mammalian species are becoming understood.

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Aphid’s Genome Reflects Its Reproductive, Symbiotic Lifestyle

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Colony of young aphids.

Aphids could be considered the “mosquitoes” of the plant world, depending on the “blood” of plants to survive. They live in symbiosis with bacteria that pass from one generation to the next, producing essential amino acids. Aphids with the same genotype can be wingless or winged. In different seasons, they develop as asexual females who produce offspring with identical genes through parthenogenesis. When temperatures drop, they can give birth to males who then fertilize the eggs laid by females.

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Evolutionary Game of Rock-Paper-Scissors May Lead to New Species

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Side-blotched lizards have three color morphs with different mating strategies, but in some populations only one morph occurs.

New research on lizards supports an old idea about how species can originate. Morphologically distinct types are often found within species, and biologists have speculated that these “morphs” could be the raw material for speciation. What were once different types of individuals within the same population could eventually evolve into separate species.

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Surprising New Branches on Arthropod Family Tree

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Centipede.

Any way you look at it — by sheer weight, species diversity or population — the hard-shelled, joint-legged creepy crawlies called arthropods dominate planet Earth. Because of their success and importance, scientists have been trying for decades to out the family relationships that link lobsters to millipedes and cockroaches to tarantulas and find which might have come first.

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How the Butterflies Got Their Spots

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Mimetic races of Heliconius erato (left) and Heliconius melpomene (right) from the Tarapoto area of Peru.

How two butterfly species have evolved exactly the same striking wing colour and pattern has intrigued biologists since Darwin’s day. Now, scientists at Cambridge have found “hotspots” in the butterflies’ genes that they believe will explain one of the most extraordinary examples of mimicry in the natural world.

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Developmental Delay May Explain Behavior of Easygoing Bonobo Apes

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Bonobo relaxing on a branch.

New research suggests that evolutionary changes in cognitive development underlie the extensive social and behavioral differences that exist between two closely related species of great apes. The study, published online on January 28th in Current Biology, a Cell Press publication, enhances our understanding of our two closest living relatives, chimpanzees and the lesser-known bonobos, and may provide key insight into human evolution.

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Value of Sexual Reproduction Versus Asexual Reproduction

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Sexual vs. asexual reproduction – Only the snail’s hairdresser knows for sure

Living organisms have good reason for engaging in sexual, rather than asexual, reproduction according to Maurine Neiman, assistant professor of biology in the UI College of Liberal Arts and Sciences and researcher in the Roy J. Carver Center for Genomics.

The study looked at sexual, as well as asexual, varieties of a New Zealand freshwater snail, Potamopyrgus antipodarum, by sequencing mitochondrial genomes and found that the sexually reproducing snails had accumulated harmful DNA mutations at about half the rate of the asexual snails.

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Understanding Why Leopards Can’t Change Their Spots

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Leopard. The leopard cannot change its spots, nor can the tiger change its stripes, but new research tells us something about how cats end up with their spots and stripes.

The leopard cannot change its spots, nor can the tiger change its stripes, but a new research report published in the January 2010 issue of the journal Genetics tells us something about how cats end up with their spots and stripes. It demonstrates for the first time that at least three different genes are involved in the emergence of stripes, spots, and other markings on domestic cats.

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Female Fruit Flies Can Be ‘Too Attractive’ to Males, Scientists Show

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These are fruit flies courting.

Females can be too attractive to the opposite sex — too attractive for their own good — say biologists at UC Santa Barbara. They found that, among fruit flies, too much male attention directed toward attractive females leads to smaller families and, ultimately, to a reduced rate of population-wide adaptive evolution.

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