It’s truly odd to hear a creationist make a population genetics argument–an idiotic one no less. Rick Warren, evangelist and who will be leading the invocation at Obama’s inauguration, says the following about homosexuality:
Warren, a creationist, believes that homosexuality disproves evolution; he told CNN’s Larry King in 2005, “If Darwin was right, which is survival of the fittest then homosexuality would be a recessive gene because it doesn’t reproduce and you would think that over thousands of years that homosexuality would work itself out of the gene pool.”
The stupidity permeates every clause of this sentence. I really thought we wouldn’t have to take these morons seriously anymore.
Fisk away.
mikethemadbiologist
Not much of a fisk, but maybe I’m first?!!
1) Homosexuality may have a positive aspect that promotes fitness, or
2) Homosexuality may have neither a positive or negative association, and survives by “accident”, since a mutation can survive as long as it does not negatively impact the creature/species (and no, Mr Warren, stoning gays does not count as a negative impact in this sense), or
3) Homosexuality might be the product of multiple genes, and any of these could have a benefit, thus ensuring the survival of the genes as a side effect
That’s three off the top of my head.
among other things, he hasn’t a clue what a “recessive” gene is. i gather he means “surpressed”, i.e. not getting passed on to the next generation. which could be accurate except 1) gay people CAN and DO reproduce, and 2) gay people are a likely as anyone else to have reproductive siblings, so the same gene can still be passed on
i can’t tell if Warren is trying to say “a genetic basis for homosexuality disproves evolution” or “evolution disproves a genetic basis homosexuality”. i guess it doesn’t matter: stupid is stupid
To be overly specific, genes don’t code for behavior, they code for proteins. And proteins are expressed inside of incredibly complex cells and cells are parts of tissues and tissues are parts of organs and organs are parts of humans. Humans then interact with their environment to produce behavior. A complex social behavior like homosexuality is certainly polygenic and multifactorial. In a large population, selection pressure acts on each of the contributing genes independently. A putative constellation of alleles that produces homosexuality may be advantageous for other reasons.
And why does everybody assume that gay people never reproduce?
Probably Warren just is too ignorant to know that homosexuality isn’t genetic, its developemental in the fetus.
What does Mr. Warren think postmenopausal women are still living for, then? Shouldn’t evolution have programmed women to die at age 50?
And yeah, +1 what Will TS said. One of my college friends grew up in an Amish family that did not approve of homosexuality. He married and had three kids by means of a rich fantasy life before finally telling his wife that he loved her very much but was leaving her anyway.
Oh god.
That’s hilarious and wrong on so many levels… but it’s quite bizarre. Is Warren admitting that homosexuality is an inborn trait that is not merely a “lifestyle choice”, as so many of his friends would say?
When it comes to passing on genes, two nephews are as good as one son.
What does Mr. Warren think postmenopausal women are still living for, then? Shouldn’t evolution have programmed women to die at age 50?
And yeah, +1 what Will TS said. One of my college friends grew up in an Amish family that did not approve of homosexuality. He married and had three kids by means of a rich fantasy life before finally telling his wife that he loved her very much but was leaving her anyway.
If a tendency toward homosexuality is genetic in origin, it is possible that it could be like the gene causing sickle cell anemia, i.e. the presence of a recessive homosexual gene could have a positive selection value for some as yet undetermined reason. Thus, the recessive sickle cell anemia gene provides resistance to malaria.
I have a vague recollection that someone, years ago, addressed this concern in some detail. I want to say E. O. Wilson, but I’m not sure.
E.O. Wilson de-emphasized the role of culture in affecting human behaviour too much… I think I’m thinking of the guy who wanted to replace the social sciences…
Regardless, this is ridiculous. There are more possible explanations for this disease… I bet he says the same thing about Schizophrenia, “if Darwin was right they would all be gone now!”, does he even acknowledge the genes can be passed down? (do creationists understand frequency dependence?)
A general comment: An ignorant wiseman askes questions. An ignorant fool makes statements.
I am personally disapointed because I THOUGHT science was going to be a leading factor in this new preznitzy. BAH AND DAMNIT!
Did he just admit people o not choose to be gay? Get thine bullshit straight, Rick!
If a tendency toward homosexuality is genetic in origin, it is possible that it could be like the gene causing sickle cell anemia, i.e. the presence of a recessive homosexual gene could have a positive selection value for some as yet undetermined reason.
I’m not a biologist, so I’m certainly at risk of saying something really stupid. But here goes. Humans are social animals, so traits that promote cooperation in society may be more beneficial than traits that make an individual more competitive. If the genetic traits associated with homosexuality also promote greater cooperation, then societies with more homosexuality would be more successful and create higher populations. So while many homosexuals might not reproduce, they may cause society as a whole to reproduce more. Ultimately, that should encourage those genetic traits to remain in the gene pool. That said, I’d be interested to hear what a real biologist has to say about it.
Algoritmi genetici. Pietà nella nuova vita.
da Caos, segnali e visioni
di Alberto Fortunato
Lo spazio dato dalla letteratura scientifica agli algoritmi genetici, almeno in Italia, sembra davvero esiguo. Per trovarne da leggere devo fare click sulla ricerca avanzata in google. In libreria, invece, mi dicono che “…non hanno testi di biologia…” oppure “ …per la medicina devo guardare lì, in fondo a destra”. Annuisco, metto le mani nel cappotto e vado a leggere il dizionario del corpo umano. Devo passare il tempo.
L’algoritmo genetico chi lo usa? Lo usano i ricercatori. Quelli che, prendendo spunto dalla selezione naturale di Darwin, progettano e realizzano uno strumento di ricerca. Lo strumento, a mio avviso molto stimolante dal punto del coinvolgimento interdisciplinare nell’ambito della sua progettazione, è l’emblema di un ambiente di ricerca teso al miglioramento continuo. Un ambiente che lavorando con i classici tools stocastici e “aleatori” per necessità, è sempre alla ricerca di una possibile ottimizzazione.
In questi ambienti, specialmente dove ricerco io, la perfezione non esiste. Esiste un punto che, nel tempo, costituisce un punto di arrivo e di immediata ripartenza per un altro, ancora più ambizioso. Tutte le popolazioni possono essere investigate dall’algoritmo genetico? Si. In un certo senso si, purché si tratti di popolazioni di soluzioni. Se nella biologia studiamo popolazioni e campioni di animali e individui, nella ricerca che utilizza l’algoritmo genetico dobbiamo sostituire le soluzioni dei problemi agli individui della popolazione. Parlare di “evoluzione” significa indicare una popolazione di soluzioni migliori rispetto alla popolazione costituita dalle soluzioni precedenti.
Il parallelismo con la logica biologica dell’evoluzione e della “selezione naturale” si ripropone più forte quando si parla di generazione. In realtà con l’algoritmo genetico, dalla popolazione di soluzioni originarie, vengono selezionate delle soluzioni più promettenti perché queste si combinino e diano vita ad una nuova generazione di “soluzioni migliori”. Il livello di Fitness è quello che concorre ad ordinare in maniera crescente le soluzioni per consentire, ad un certo punto della sequenza, un taglio di quelle meno interessanti. Con il passaggio generazionale da una popolazione di soluzioni a quella successiva avviene ovviamente una trasmissione (solo una parte) del patrimonio genetico. Le soluzioni genitori migliori lasciano, alle soluzioni figlie, parte della loro costituzione genetica.
Due cose ancora sono importanti in questo passaggio generazionale. Si tratta delle due cose che mi intrigano di più. Di queste non dobbiamo trascurare alcun aspetto, sia dal punto di vista filosofico che dal punto di vista operativo e tecnico sperimentale: la mutazione genetica vista nella sua “casualità” e il “crossover” visto nel suo determinismo.
La mutazione genetica avviene con una modifica casuale di alcune parti di geni con valore di fitness più basso. La mutazione genetica delle soluzioni non dà alcun risultato in termini di reale miglioramento. Quel che può essere un risultato di fitness più elevato infatti non deve essere considerato un passaggio evolutivo certo. E’ discutibile, in un’ottica di popolazione di soluzioni, pensare ad una evoluzione in presenza di una mutazione genetica. Con la mutazione possiamo sempre trovarci di fronte ad un ottimo locale ( si badi bene che ottimo locale non è ottimo assoluto) e cioè un risultato migliore ma ancora perfezionabile.
Con il crossover mettiamo le mani sul caso. E qui cominciano i problemi. Soprattutto quando si parla di popolazioni di soluzioni. Paradossalmente. Sogno. Vedo. Sento.
Sono nella stanzetta di Tommy. Estraggo il set delle soluzioni dal gold box e ne srotolo una. La prendo a caso? Non so. La dispiego sul letto e ne ammiro la costituzione genetica. Merita. Le trovo un compagno e affianco gli individui in modo da poterne ammirare il parallelismo. Tommy mi passa il bisturi e comincia il mio dilemma. Dove taglio? Qual è sarà il punto in cui il fendente avrà casualmente determinato l’evoluzione di una specie di soluzioni migliori. Testa e coda. Zac. Un colpo secco e seziono le soluzioni a metà. Taglio (a caso?) le stringhe di codifica e ottengo due teste e due code. Ancora si muovono. Vibrano nello spazio antistante due battiti di ali di farfalla che porteranno le vicissitudini del Mondo lontano dagli universi probabili fin’ora definiti. Scambio teste e code. Nuovi geni. Nuove visioni. Nuova vita. Il Signore abbia pietà di me anche in questa.
di Alberto Fortunato
Algoritmi Genetici. Pietà nella nuova vita.
Da Caos, segnali e visioni
Lora- that was hilarious!
I believe that homosexuality is a combination of genetic changes; whether mutation or evolution for purposes eluded to by fostert or… possibly a prenatal development as by Robert Jase (or a combination of the two.) Isn’t there some relevance to the ‘good of all’ evolutionary theories through? As homosexuality is relatively predominant in society ~ and has been throughout history, I would lean towards the idea that there are species benefits from these varied genetics.
I just searched and searched as I swore I read an article on a Bacteria yesterday that only some of the bacteria excrete a goo that floats; while all the others have to depend on that goo to float as well (the minority being the goo producers, without whom, the entire colony would sink in the liquid and die ~ but alas, I cannot find it) I did however find this article on group selection;
http://www.sciam.com/article.cfm?id=whats-good-for-the-group
…and the following article that may or may not be related – that I plan to read 🙂
http://biology.plosjournals.org/perlserv/?doi=10.1371/journal.pbio.0060014&request=get-document&ct=1
KAS
Sexuality is complex behavior. Hardly the stuff to be determined by a single gene, but rather determined by the interplay of many. It is hard to believe that sexuality could be explained by simple Mendelian genetics because it is hard to fathom it as anything less than an astoundingly polygenic trait. If this is so, then its heritability would not be describe in terms such as recessive or dominant and natural selection could not be applied in such simplistic terms as described by Warren above. I don’t think we are talking about a loss of function mutation in a single alelle in other words.
Just wanted to further my comment by adding in a little of what Will TS said. Like I said, behavior is likely polygenic. TS said that each of those genes is selected independently. Therefore all of the genes that together confer homosexuality, may be positively selected. When they come together in one individual they may cause homosexual behavior. So because homosexuality is not a trait determined by a single alelle or a few like eye color in drosophila, it won’t be selected against by natural selection like a single trait would be. Instead all of the alleles must be treated as separately selected. Additionaly, there may be a spectrum of alleles that are at play here rather than just a single combo.
That’s hilarious and wrong on so many levels… but it’s quite bizarre. Is Warren admitting that homosexuality is an inborn trait that is not merely a “lifestyle choice”, as so many of his friends would say?