Podcast #128: We chat with Kent C Dodds about why he loves React and discuss what life was like in the dark days before Git. Listen now.
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This is a interesting question and for a long time it was thought that they do not age. In the meantime there are some new papers which say that bacteria do indeed age. Aging can be defined as the accumulation of non-genetic damages (for example oxidative damage to proteins) over time. If too much of these damages are accumulated, the cell will eventually ...


39

According to Cornell's All About Birds website, you will have to wait about a month for the nest to be cleared. The egg incubation period is 12–14 days. Following hatching, the nestlings will remain in the nest for another 13 days (i.e., the "nestling period" is 13 days). However, there are two caveats to this: A typical robin clutch size (i.e. the # of ...


32

Bacteria such as E. coli are known to increase their mutation rate (by switching to a more error prone polymerase among other things) when under stress. This can mean being placed in a medium where it's not adapted to grow (http://www.micab.umn.edu/courses/8002/Rosenberg.pdf) or when treated with antibiotics (http://www.ncbi.nlm.nih.gov/pmc/articles/...


16

Cyanobacteria require iron for photosynthesis and can be found as fossil stromatolites dating back to 3.5 billion years ago. Stromatolites are layered structures made up of cyanobacteria and sediment. Source: https://en.wikipedia.org/wiki/Stromatolite Modern stromatolites can be found at Shark Bay in Australia, Chetumal Bay in Belize, and Laguna Bacalar ...


15

Well, this needs to be broken down into two parts. Do Crocodilians age (undergo senescence), and are Crocodilians immortal (will only die of external causes)? Are Crocodilians immortal? - No. They appear to live about as long as humans before they die. Measuring crocodile age is unreliable, although several techniques are used to derive a reasonable ...


14

The "change in reproduction age" you mention is one major aspect of life history evolution. A massive literature exists on this topic, including several books: e.g., The evolution of life histories: Theory and analysis (Roff, 1992) and The evolution of life histories (Stearns, 1992). Reznick and various colleagues have carried out extensive studies of ...


14

I think this falls into your criteria but correct me if i'm wrong :). The HIV reverse transcriptase protein has evolved to have relatively low fidelity (leading to a high mutation rate in replicated virus particles). Reverse transcriptase is also recombinogenic, ie. it can switch templates during replication leading to even more variability. Combined, ...


12

Limiting the conversation to mammals, and taking relative brain size as a proxy for intelligence (which, of course is not necessarily "true", but at least is quantifiable), the answer is yes: body-size relative brain size correlates with body-size relative longevity in mammals. using a global database of 493 species, we provide evidence showing that ...


11

This isn't so precisely focused on tortoises, but a general theory in evolutionary biology for why some animals live longer is K vs r selection theory. The idea here is that animals will make a sort of evolutionary 'choice' and configure themselves to breed as numerously and quickly as they can. This is called 'r' selection, named after the constant that ...


11

It looks like sustained or consistent moisture might be (at least part of) the phenological cue for flowering: The wikipedia article mentions that consistent humidity will induce flowering in at least some species and cites Fernández-Alonso & Groenendijk (2004), which says: It generally flowers after the rainy periods, but in humid pastures and under ...


8

Species have been observed in controlled experiments to use different sources of energy, for instance axenic E. coli cultures picking up citrate metabolism in Lenski's Lab at MSU. They have also shown that mutations to the mutator gene mutT can accelerate the process of evolution, though it's evolution directed by fitness in a very specific setting.


8

Short answer: Changing something (instead of everything) yes. There are several studies on the impact of environmental factors on life span. Of course it depends from organism to organism. Diet restriction for example has been shown to extend life span of worms and mice. Temperature is also working well, at least with microorganisms, the metabolism of E....


8

From wiki: Most amphibians lay their eggs in water and have aquatic larvae that undergo metamorphosis to become terrestrial adults This suggests clearly that not all of them do so. Here are a few interesting cases I could think of: The common midwife toad carry the eggs on their back. The eggs are not necessarily submerged by water then. To my ...


7

There is no color code for the leafs - the color results from biochemical reactions. Basically there are three colors: Green, yellow and red. Green color is caused by the chlorophyll inside the chloroplasts, when the leafs are active in photosynthesis. Yellow color is caused by Carotenoids, which are present in the leafs all the time, but are masked by the ...


7

As you indicate in your question, the average age of sexual maturity is probably the best way to approach this, since immaturity is usually how juveniles are defined. Age of puberty is also different in boys and girls (the same goes for many animals), and has also decreased in the 21 century. However, as an historical average for humans 15 years is probably ...


6

Three important concepts about abiogenesis Let's start with three important concepts Definition of life You'll need to give a good definition of life, because biologists actually don't have one (it is a matter of philosophy to define life, not biology). Time it took for life to emerge Life as we know it emerged only after a huge period of time (hundreds ...


5

Yes, at least some fishes have intrinsic lifespans and deaths that are related to their own life-history and not to external forces such as predation or disease. Fishes show three types of senescence. Lampreys, eels and pacific salmon exhibit rapid senescence and sudden death at first spawning. The guppy, red panchax, medaka, platyfish, Indian murrel ...


5

Many species of Eel (order Anguilliformes) have a semelparous life history (most species? all?), i.e. they only reproduce once and then die (as opposed to an iteroparous life history). Many species are now threatened by extinction (e.g. American eel and European eel), since they have been heavily exploited by fisheries and they are also vulnerable to habitat ...


5

Have you tried the Ecological Data Wiki? It's an NSF-funded repository of links to ecological databases and datasets: Main page: http://ecologicaldata.org Find data tab, refined to Taxon=Birds, Ecological level=Species: https://ecologicaldata.org/search?f[0]=taxonomy_vocabulary_2%253Aname%3ABirds&f[1]=taxonomy_vocabulary_6%253Aname%3ASpecies The '...


5

It's a nice question, I've tried looking for research papers to no avail. But I will add a few things that I hope will help: Firstly, tap water's composition is quite different from rain water- two criteria for distinction that come to mind would be pH and TDS, details follow: Tap water has a higher TDS (total dissolved solids)than rain water, making it ...


5

Basic misunderstand about how one can make sense of nature Nature is not a conscient being (or at least not falsifiable conscient being) trying to optimize the amount of flora or whatever you would like to optimize. There is no conscious will in the processes of evolution, in the course of a meteorite or in the decay rate of some radioactive material. ...


5

We are only barely beginning to understand how the brain works, including memory. We do know that it is a very complex thing. There are many different kinds of memory; many different processes are involved in creating and recalling memories. One factor that plays into a naïve concept of "how old a memory is" is that "remembering" does not seem to be a ...


5

Summary It has been proposed that iron was indeed important for the first life on earth, specifically in combination with sulphur. This is because conditions are thought to have existed in volcanic hydrothermal vents that would have allowed formation of iron–sulphur complexes which perform oxido-reduction reactions in modern proteins (as well as more ...


4

How about species actively changing the factors that play a role in the selection process? Humans are a species that have heavily modified this process. In the western world, we have gone away from selection by survival skills and genetic fitness to move to a social selection, where genome is secondary to social skills and adaptation to fashion, which are ...


4

This question can be tackled in several ways, and also seems to contain a couple of misconceptions about ecological processes (e.g. problematic group-selection ideas and how species 'fit' into the ecosystem). However, I think it is most usefully answered from the perspective of life history theory and the evolution of life histories (see e.g. Roff, 2002 and ...


4

There are two important points here: The adult phase is defined as the phase during which reproduction occurs. It is therefore impossible for reproduction not to occur during the adult phase as you would immediately call this phase the adult phase. Because of this purely semantic issue (nothing to do with biology) the answer to your question is necessarily "...


3

Therapeutic hypothermia certainly is an extremely useful short-term treatment for hypoxic and ischaemic injury to tissues (caused by loss of blood flow and/or oxygen) and is part of the protocol for treating people in intensive care who have had out of hospital cardiac or respiratory arrest as well as being used during heart surgery in cardiopulmonary bypass....


3

Here is a quite nice Chemistry of Autumn Leaf Color. And here is a less chemical, but more detailed explanation regarding the triggering of colour change, which is quite similar to the one from the University of Illinois that @Oreotrephes already gave. As I understand it, during sunny days a lot of chlorophyll is broken down, but also built up. When after ...


3

Everything has a life span. When it comes to trees, there are significant variations between species (see here some examples). Apart from the external factors, these variations seem to be related to telomeres length and telomerase activity [1]: The results from this study support the hypothesis that both increased telomere length and telomerase activity ...


3

The answer to this could be that there are many factors contributing to the length of the life of tree species. Climate: You can see that trees that have a reputation of becoming really old live in environments that have low moisture levels and much sunlight over the course of the year. For example, you can see that the most long-lived trees in America ...


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